Textile seal-forming structure with multiple curvatures

ABSTRACT

A patient interface including a seal-forming structure with a textile membrane that has at least one hole such that the flow of air at a therapeutic pressure is delivered to at least an entrance to the patient&#39;s nares and/or an entrance to the patient&#39;s mouth. The seal-forming structure is constructed and arranged to maintain the therapeutic pressure in a cavity of a plenum chamber throughout the patient&#39;s respiratory cycle, in use. The textile membrane includes a first portion that is held in a relaxed state and a second portion that is held in a taut state. The taut state of the second portion is configured to allow the seal-forming structure to include a three-dimensional shape that has multiple curvatures.

A portion of the disclosure of this patent document contains materialwhich is subject to copyright protection. The copyright owner has noobjection to the facsimile reproduction by anyone of the patent documentor the patent disclosure, as it appears in Patent Office patent files orrecords, but otherwise reserves all copyright rights whatsoever.

1 CROSS-REFERENCE TO RELATED APPLICATIONS

This a continuation of U.S. application Ser. No. 18/187,761, filed Mar.22, 2023, which is a continuation of U.S. application Ser. No.17/769,685, filed Apr. 15, 2022, now U.S. Pat. No. 11,648,364, which isthe U.S. national phase of International Application No.PCT/AU2020/051109 filed Jul. 9, 2020 which designated the U.S. andclaims priority to AU 2020902371 filed Jul. 9, 2020, and is acontinuation-in-part of U.S. application Ser. No. 16/850,803, filed Apr.16, 2020, which is a continuation-in-part of International ApplicationNo. PCT/IB2019/058832, the entire contents of each of which are herebyincorporated by reference.

International Application No. PCT/IB2019/058832 claims the benefit ofU.S. Provisional Application No. 62/805,147, filed Feb. 13, 2019, andalso claims the benefit of Australian Provisional Application Nos.AU2018904886, filed Dec. 21, 2018, and AU2018903752, filed Oct. 16,2018, each of which is also hereby incorporated herein by reference intheir entirety.

2 BACKGROUND OF THE TECHNOLOGY 2.1 Field of the Technology

The present technology relates to one or more of the screening,diagnosis, monitoring, treatment, prevention and amelioration ofrespiratory-related disorders. The present technology also relates tomedical devices or apparatus, and their use.

2.2 Description of the Related Art 2.2.1 Human Respiratory System andits Disorders

The respiratory system of the body facilitates gas exchange. The noseand mouth form the entrance to the airways of a patient.

The airways include a series of branching tubes, which become narrower,shorter and more numerous as they penetrate deeper into the lung. Theprime function of the lung is gas exchange, allowing oxygen to move fromthe inhaled air into the venous blood and carbon dioxide to move in theopposite direction. The trachea divides into right and left mainbronchi, which further divide eventually into terminal bronchioles. Thebronchi make up the conducting airways, and do not take part in gasexchange. Further divisions of the airways lead to the respiratorybronchioles, and eventually to the alveoli. The alveolated region of thelung is where the gas exchange takes place, and is referred to as therespiratory zone. See “Respiratory Physiology”, by John B. West,Lippincott Williams & Wilkins, 9th edition published 2012.

A range of respiratory disorders exist. Certain disorders may becharacterised by particular events, e.g. apneas, hypopneas, andhyperpneas.

Examples of respiratory disorders include Obstructive Sleep Apnea (OSA),Cheyne-Stokes Respiration (CSR), respiratory insufficiency, ObesityHyperventilation Syndrome (OHS), Chronic Obstructive Pulmonary Disease(COPD), Neuromuscular Disease (NMD) and Chest wall disorders.

Obstructive Sleep Apnea (OSA), a form of Sleep Disordered Breathing(SDB), is characterised by events including occlusion or obstruction ofthe upper air passage during sleep. It results from a combination of anabnormally small upper airway and the normal loss of muscle tone in theregion of the tongue, soft palate and posterior oropharyngeal wallduring sleep. The condition causes the affected patient to stopbreathing for periods typically of 30 to 120 seconds in duration,sometimes 200 to 300 times per night. It often causes excessive daytimesomnolence, and it may cause cardiovascular disease and brain damage.The syndrome is a common disorder, particularly in middle agedoverweight males, although a person affected may have no awareness ofthe problem. See U.S. Pat. No. 4,944,310 (Sullivan).

Respiratory failure is an umbrella term for respiratory disorders inwhich the lungs are unable to inspire sufficient oxygen or exhalesufficient CO 2 to meet the patient's needs. Respiratory failure mayencompass some or all of the following disorders.

A patient with respiratory insufficiency (a form of respiratory failure)may experience abnormal shortness of breath on exercise.

A range of therapies have been used to treat or ameliorate suchconditions. Furthermore, otherwise healthy individuals may takeadvantage of such therapies to prevent respiratory disorders fromarising. However, these have a number of shortcomings.

2.2.2 Therapies

Various respiratory therapies, such as Continuous Positive AirwayPressure (CPAP) therapy, Non-invasive ventilation (NIV), Invasiveventilation (IV), and High Flow Therapy (HFT) have been used to treatone or more of the above respiratory disorders.

2.2.2.1 Respiratory Pressure Therapies

Respiratory pressure therapy is the application of a supply of air to anentrance to the airways at a controlled target pressure that isnominally positive with respect to atmosphere throughout the patient'sbreathing cycle (in contrast to negative pressure therapies such as thetank ventilator or cuirass).

Continuous Positive Airway Pressure (CPAP) therapy has been used totreat Obstructive Sleep Apnea (OSA). The mechanism of action is thatcontinuous positive airway pressure acts as a pneumatic splint and mayprevent upper airway occlusion, such as by pushing the soft palate andtongue forward and away from the posterior oropharyngeal wall. Treatmentof OSA by CPAP therapy may be voluntary, and hence patients may electnot to comply with therapy if they find devices used to provide suchtherapy one or more of: uncomfortable, difficult to use, expensive andaesthetically unappealing.

2.2.2.2 Flow Therapies

Not all respiratory therapies aim to deliver a prescribed therapeuticpressure. Some respiratory therapies aim to deliver a prescribedrespiratory volume, by delivering an inspiratory flow rate profile overa targeted duration, possibly superimposed on a positive baselinepressure. In other cases, the interface to the patient's airways is‘open’ (unsealed) and the respiratory therapy may only supplement thepatient's own spontaneous breathing with a flow of conditioned orenriched gas. In one example, High Flow therapy (HFT) is the provisionof a continuous, heated, humidified flow of air to an entrance to theairway through an unsealed or open patient interface at a “treatmentflow rate” that is held approximately constant throughout therespiratory cycle. The treatment flow rate is nominally set to exceedthe patient's peak inspiratory flow rate. HFT has been used to treatOSA, CSR, respiratory failure, COPD, and other respiratory disorders.One mechanism of action is that the high flow rate of air at the airwayentrance improves ventilation efficiency by flushing, or washing out,expired CO₂ from the patient's anatomical deadspace. Hence, HFT is thussometimes referred to as a deadspace therapy (DST). Other benefits mayinclude the elevated warmth and humidification (possibly of benefit insecretion management) and the potential for modest elevation of airwaypressures. As an alternative to constant flow rate, the treatment flowrate may follow a profile that varies over the respiratory cycle.

Another form of flow therapy is long-term oxygen therapy (LTOT) orsupplemental oxygen therapy. Doctors may prescribe a continuous flow ofoxygen enriched air at a specified oxygen concentration (from 21%, theoxygen fraction in ambient air, to 100%) at a specified flow rate (e.g.,1 litre per minute (LPM), 2 LPM, 3 LPM, etc.) to be delivered to thepatient's airway.

2.2.2.3 Supplementary Oxygen

For certain patients, oxygen therapy may be combined with a respiratorypressure therapy or HFT by adding supplementary oxygen to thepressurised flow of air. When oxygen is added to respiratory pressuretherapy, this is referred to as RPT with supplementary oxygen. Whenoxygen is added to HFT, the resulting therapy is referred to as HFT withsupplementary oxygen.

2.2.3 Respiratory Therapy Systems

These respiratory therapies may be provided by a respiratory therapysystem or device. Such systems and devices may also be used to screen,diagnose, or monitor a condition without treating it.

A respiratory therapy system may comprise a Respiratory Pressure TherapyDevice (RPT device), an air circuit, a humidifier, a patient interface,an oxygen source, and data management.

2.2.3.1 Patient Interface

A patient interface may be used to interface respiratory equipment toits wearer, for example by providing a flow of air to an entrance to theairways. The flow of air may be provided via a mask to the nose and/ormouth, a tube to the mouth or a tracheostomy tube to the trachea of apatient. Depending upon the therapy to be applied, the patient interfacemay form a seal, e.g., with a region of the patient's face, tofacilitate the delivery of gas at a pressure at sufficient variance withambient pressure to effect therapy, e.g., at a positive pressure ofabout 10 cmH₂O relative to ambient pressure. For other forms of therapy,such as the delivery of oxygen, the patient interface may not include aseal sufficient to facilitate delivery to the airways of a supply of gasat a positive pressure of about 10 cmH₂O. For flow therapies such asnasal HFT, the patient interface is configured to insufflate the naresbut specifically to avoid a complete seal. One example of such a patientinterface is a nasal cannula.

Certain other mask systems may be functionally unsuitable for thepresent field. For example, purely ornamental masks may be unable tomaintain a suitable pressure. Mask systems used for underwater swimmingor diving may be configured to guard against ingress of water from anexternal higher pressure, but not to maintain air internally at a higherpressure than ambient.

Certain masks may be clinically unfavourable for the present technologye.g. if they block airflow via the nose and only allow it via the mouth.

Certain masks may be uncomfortable or impractical for the presenttechnology if they require a patient to insert a portion of a maskstructure in their mouth to create and maintain a seal via their lips.

Certain masks may be impractical for use while sleeping, e.g. forsleeping while lying on one's side in bed with a head on a pillow.

The design of a patient interface presents a number of challenges. Theface has a complex three-dimensional shape. The size and shape of nosesand heads varies considerably between individuals. Since the headincludes bone, cartilage and soft tissue, different regions of the facerespond differently to mechanical forces. The jaw or mandible may moverelative to other bones of the skull. The whole head may move during thecourse of a period of respiratory therapy.

As a consequence of these challenges, some masks suffer from being oneor more of obtrusive, aesthetically undesirable, costly, poorly fitting,difficult to use, and uncomfortable especially when worn for longperiods of time or when a patient is unfamiliar with a system. Wronglysized masks can give rise to reduced compliance, reduced comfort andpoorer patient outcomes. Masks designed solely for aviators, masksdesigned as part of personal protection equipment (e.g. filter masks),SCUBA masks, or for the administration of anaesthetics may be tolerablefor their original application, but nevertheless such masks may beundesirably uncomfortable to be worn for extended periods of time, e.g.,several hours. This discomfort may lead to a reduction in patientcompliance with therapy. This is even more so if the mask is to be wornduring sleep.

CPAP therapy is highly effective to treat certain respiratory disorders,provided patients comply with therapy. If a mask is uncomfortable, ordifficult to use a patient may not comply with therapy. Since it isoften recommended that a patient regularly wash their mask, if a mask isdifficult to clean (e.g., difficult to assemble or disassemble),patients may not clean their mask and this may impact on patientcompliance.

While a mask for other applications (e.g. aviators) may not be suitablefor use in treating sleep disordered breathing, a mask designed for usein treating sleep disordered breathing may be suitable for otherapplications.

For these reasons, patient interfaces for delivery of CPAP during sleepform a distinct field.

2.2.3.1.1 Seal-Forming Structure

Patient interfaces may include a seal-forming structure. Since it is indirect contact with the patient's face, the shape and configuration ofthe seal-forming structure can have a direct impact the effectivenessand comfort of the patient interface.

A patient interface may be partly characterised according to the designintent of where the seal-forming structure is to engage with the face inuse. In one form of patient interface, a seal-forming structure maycomprise a first sub-portion to form a seal around the left naris and asecond sub-portion to form a seal around the right naris. In one form ofpatient interface, a seal-forming structure may comprise a singleelement that surrounds both nares in use. Such single element may bedesigned to for example overlay an upper lip region and a nasal bridgeregion of a face. In one form of patient interface a seal-formingstructure may comprise an element that surrounds a mouth region in use,e.g. by forming a seal on a lower lip region of a face. In one form ofpatient interface, a seal-forming structure may comprise a singleelement that surrounds both nares and a mouth region in use. Thesedifferent types of patient interfaces may be known by a variety of namesby their manufacturer including nasal masks, full-face masks, nasalpillows, nasal puffs and oro-nasal masks.

A seal-forming structure that may be effective in one region of apatient's face may be inappropriate in another region, e.g. because ofthe different shape, structure, variability and sensitivity regions ofthe patient's face. For example, a seal on swimming goggles thatoverlays a patient's forehead may not be appropriate to use on apatient's nose.

Certain seal-forming structures may be designed for mass manufacturesuch that one design fit and be comfortable and effective for a widerange of different face shapes and sizes. To the extent to which thereis a mismatch between the shape of the patient's face, and theseal-forming structure of the mass-manufactured patient interface, oneor both must adapt in order for a seal to form.

One type of seal-forming structure extends around the periphery of thepatient interface, and is intended to seal against the patient's facewhen force is applied to the patient interface with the seal-formingstructure in confronting engagement with the patient's face. Theseal-forming structure may include an air or fluid filled cushion, or amoulded or formed surface of a resilient seal element made of anelastomer such as a rubber. With this type of seal-forming structure, ifthe fit is not adequate, there will be gaps between the seal-formingstructure and the face, and additional force will be required to forcethe patient interface against the face in order to achieve a seal.

Another type of seal-forming structure incorporates a flap seal of thinmaterial positioned about the periphery of the mask so as to provide aself-sealing action against the face of the patient when positivepressure is applied within the mask. Like the previous style of sealforming portion, if the match between the face and the mask is not good,additional force may be required to achieve a seal, or the mask mayleak. Furthermore, if the shape of the seal-forming structure does notmatch that of the patient, it may crease or buckle in use, giving riseto leaks.

Another type of seal-forming structure may comprise a friction-fitelement, e.g. for insertion into a naris, however some patients findthese uncomfortable.

Another form of seal-forming structure may use adhesive to achieve aseal. Some patients may find it inconvenient to constantly apply andremove an adhesive to their face.

A range of patient interface seal-forming structure technologies aredisclosed in the following patent applications, assigned to ResMedLimited: WO 1998/004,310; WO 2006/074,513; WO 2010/135,785.

One form of nasal pillow is found in the Adam Circuit manufactured byPuritan Bennett. Another nasal pillow, or nasal puff is the subject ofU.S. Pat. No. 4,782,832 (Trimble et al.), assigned to Puritan-BennettCorporation.

ResMed Limited has manufactured the following products that incorporatenasal pillows: SWIFT™ nasal pillows mask, SWIFT™ II nasal pillows mask,SWIFT™ LT nasal pillows mask, SWIFT™ FX nasal pillows mask and MIRAGELIBERTY™ full-face mask. The following patent applications, assigned toResMed Limited, describe examples of nasal pillows masks: InternationalPatent Application WO2004/073,778 (describing amongst other thingsaspects of the ResMed Limited SWIFT™ nasal pillows), US PatentApplication 2009/0044808 (describing amongst other things aspects of theResMed Limited SWIFT™ LT nasal pillows); International PatentApplications WO 2005/063,328 and WO 2006/130,903 (describing amongstother things aspects of the ResMed Limited MIRAGE LIBERTY™ full-facemask); International Patent Application WO 2009/052,560 (describingamongst other things aspects of the ResMed Limited SWIFT™ FX nasalpillows).

2.2.3.1.2 Positioning and stabilising

A seal-forming structure of a patient interface used for positive airpressure therapy is subject to the corresponding force of the airpressure to disrupt a seal. Thus a variety of techniques have been usedto position the seal-forming structure, and to maintain it in sealingrelation with the appropriate portion of the face.

One technique is the use of adhesives. See for example US PatentApplication Publication No. US 2010/0000534. However, the use ofadhesives may be uncomfortable for some.

Another technique is the use of one or more straps and/or stabilisingharnesses. Many such harnesses suffer from being one or more ofill-fitting, bulky, uncomfortable and awkward to use.

2.2.3.2 Respiratory Pressure Therapy (RPT) Device

A respiratory pressure therapy (RPT) device may be used individually oras part of a system to deliver one or more of a number of therapiesdescribed above, such as by operating the device to generate a flow ofair for delivery to an interface to the airways. The flow of air may bepressure-controlled (for respiratory pressure therapies) orflow-controlled (for flow therapies such as HFT). Thus RPT devices mayalso act as flow therapy devices. Examples of RPT devices include a CPAPdevice and a ventilator.

Air pressure generators are known in a range of applications, e.g.industrial-scale ventilation systems. However, air pressure generatorsfor medical applications have particular requirements not fulfilled bymore generalised air pressure generators, such as the reliability, sizeand weight requirements of medical devices. In addition, even devicesdesigned for medical treatment may suffer from shortcomings, pertainingto one or more of: comfort, noise, ease of use, efficacy, size, weight,manufacturability, cost, and reliability.

An example of the special requirements of certain RPT devices isacoustic noise.

Table of noise output levels of prior RPT devices (one specimen only,measured using test method specified in ISO 3744 in CPAP mode at 10cmH₂O).

A-weighted sound Year RPT Device name pressure level dB(A) (approx.)C-Series Tango ™ 31.9 2007 C-Series Tango ™ with Humidifier 33.1 2007 S8Escape ™ II 30.5 2005 S8 Escape ™ II with H4i™M Humidifier 31.1 2005 S9AutoSet ™ 26.5 2010 S9 AutoSet ™ with H5i Humidifier 28.6 2010

One known RPT device used for treating sleep disordered breathing is theS9 Sleep Therapy System, manufactured by ResMed Limited. Another exampleof an RPT device is a ventilator. Ventilators such as the ResMedStellar™ Series of Adult and Paediatric Ventilators may provide supportfor invasive and non-invasive non-dependent ventilation for a range ofpatients for treating a number of conditions such as but not limited toNMD, OHS and COPD.

The ResMed Elisée™ 150 ventilator and ResMed VS III™ ventilator mayprovide support for invasive and non-invasive dependent ventilationsuitable for adult or paediatric patients for treating a number ofconditions. These ventilators provide volumetric and barometricventilation modes with a single or double limb circuit. RPT devicestypically comprise a pressure generator, such as a motor-driven bloweror a compressed gas reservoir, and are configured to supply a flow ofair to the airway of a patient. In some cases, the flow of air may besupplied to the airway of the patient at positive pressure. The outletof the RPT device is connected via an air circuit to a patient interfacesuch as those described above.

The designer of a device may be presented with an infinite number ofchoices to make. Design criteria often conflict, meaning that certaindesign choices are far from routine or inevitable. Furthermore, thecomfort and efficacy of certain aspects may be highly sensitive tosmall, subtle changes in one or more parameters.

2.2.3.3 Air Circuit

An air circuit is a conduit or a tube constructed and arranged to allow,in use, a flow of air to travel between two components of a respiratorytherapy system such as the RPT device and the patient interface. In somecases, there may be separate limbs of the air circuit for inhalation andexhalation. In other cases, a single limb air circuit is used for bothinhalation and exhalation.

2.2.3.4 Humidifier

Delivery of a flow of air without humidification may cause drying ofairways. The use of a humidifier with an RPT device and the patientinterface produces humidified gas that minimizes drying of the nasalmucosa and increases patient airway comfort. In addition, in coolerclimates, warm air applied generally to the face area in and about thepatient interface is more comfortable than cold air.

A range of artificial humidification devices and systems are known,however they may not fulfil the specialised requirements of a medicalhumidifier.

Medical humidifiers are used to increase humidity and/or temperature ofthe flow of air in relation to ambient air when required, typicallywhere the patient may be asleep or resting (e.g. at a hospital). Amedical humidifier for bedside placement may be small. A medicalhumidifier may be configured to only humidify and/or heat the flow ofair delivered to the patient without humidifying and/or heating thepatient's surroundings. Room-based systems (e.g. a sauna, an airconditioner, or an evaporative cooler), for example, may also humidifyair that is breathed in by the patient, however those systems would alsohumidify and/or heat the entire room, which may cause discomfort to theoccupants. Furthermore, medical humidifiers may have more stringentsafety constraints than industrial humidifiers

While a number of medical humidifiers are known, they can suffer fromone or more shortcomings. Some medical humidifiers may provideinadequate humidification, some are difficult or inconvenient to use bypatients.

2.2.3.5 Data Management

There may be clinical reasons to obtain data to determine whether thepatient prescribed with respiratory therapy has been “compliant”, e.g.that the patient has used their RPT device according to one or more“compliance rules”. One example of a compliance rule for CPAP therapy isthat a patient, in order to be deemed compliant, is required to use theRPT device for at least four hours a night for at least 21 of 30consecutive days. In order to determine a patient's compliance, aprovider of the RPT device, such as a health care provider, may manuallyobtain data describing the patient's therapy using the RPT device,calculate the usage over a predetermined time period, and compare withthe compliance rule. Once the health care provider has determined thatthe patient has used their RPT device according to the compliance rule,the health care provider may notify a third party that the patient iscompliant.

There may be other aspects of a patient's therapy that would benefitfrom communication of therapy data to a third party or external system.

Existing processes to communicate and manage such data can be one ormore of costly, time-consuming, and error-prone.

2.2.3.6 Mandibular Repositioning

A mandibular repositioning device (MRD) or mandibular advancement device(MAD) is one of the treatment options for sleep apnea and snoring. It isan adjustable oral appliance available from a dentist or other supplierthat holds the lower jaw (mandible) in a forward position during sleep.The MRD is a removable device that a patient inserts into their mouthprior to going to sleep and removes following sleep. Thus, the MRD isnot designed to be worn all of the time. The MRD may be custom made orproduced in a standard form and includes a bite impression portiondesigned to allow fitting to a patient's teeth. This mechanicalprotrusion of the lower jaw expands the space behind the tongue, putstension on the pharyngeal walls to reduce collapse of the airway anddiminishes palate vibration.

In certain examples a mandibular advancement device may comprise anupper splint that is intended to engage with or fit over teeth on theupper jaw or maxilla and a lower splint that is intended to engage withor fit over teeth on the lower jaw or mandible. The upper and lowersplints are connected together laterally via a pair of connecting rods.The pair of connecting rods are fixed symmetrically on the upper splintand on the lower splint.

In such a design the length of the connecting rods is selected such thatwhen the MRD is placed in a patient's mouth the mandible is held in anadvanced position. The length of the connecting rods may be adjusted tochange the level of protrusion of the mandible. A dentist may determinea level of protrusion for the mandible that will determine the length ofthe connecting rods.

Some MRDs are structured to push the mandible forward relative to themaxilla while other MADs, such as the ResMed Narval CC™ MRD are designedto retain the mandible in a forward position. This device also reducesor minimises dental and temporo-mandibular joint (TMJ) side effects.Thus, it is configured to minimises or prevent any movement of one ormore of the teeth.

2.2.3.7 Vent Technologies

Some forms of treatment systems may include a vent to allow the washoutof exhaled carbon dioxide. The vent may allow a flow of gas from aninterior space of a patient interface, e.g., the plenum chamber, to anexterior of the patient interface, e.g., to ambient.

The vent may comprise an orifice and gas may flow through the orifice inuse of the mask. Many such vents are noisy. Others may become blocked inuse and thus provide insufficient washout. Some vents may be disruptiveof the sleep of a bed partner 1100 of the patient 1000, e.g. throughnoise or focused airflow.

ResMed Limited has developed a number of improved mask venttechnologies. See International Patent Application Publication No. WO1998/034,665; International Patent Application Publication No. WO2000/078,381; U.S. Pat. No. 6,581,594; US Patent Application PublicationNo. US 2009/0050156; US Patent Application Publication No. 2009/0044808.

Table of noise of prior masks (ISO 17510-2:2007, 10 cmH₂O pressure at 1m)

A-weighted A-weighted sound power sound pressure Mask level dB(A) dB(A)Year Mask name type (uncertainty) (uncertainty) (approx.) Glue-on (*)nasal 50.9 42.9 1981 ResCare nasal 31.5 23.5 1993 standard (*) ResMednasal 29.5 21.5 1998 Mirage ™ (*) ResMed nasal 36 (3) 28 (3) 2000UltraMirage ™ ResMed nasal 32 (3) 24 (3) 2002 Mirage Activa ™ ResMednasal 30 (3) 22 (3) 2008 Mirage Micro ™ ResMed nasal 29 (3) 22 (3) 2008Mirage ™ SoftGel ResMed nasal 26 (3) 18 (3) 2010 Mirage ™ FX ResMednasal 37 29 2004 Mirage Swift ™ pillows (*) ResMed nasal 28 (3) 20 (3)2005 Mirage Swift ™ pillows II ResMed nasal 25 (3) 17 (3) 2008 MirageSwift ™ pillows LT ResMed AirFit nasal 21 (3) 13 (3) 2014 P10 pillows((*) one specimen only, measured using test method specified in ISO 3744in CPAP mode at 10 cmH₂O)

Sound pressure values of a variety of objects are listed below

A-weighted sound Object pressure dB(A) Notes Vacuum cleaner: Nilfisk 68ISO 3744 at Walter Broadly Litter Hog: 1 m distance B+ GradeConversational speech 60 1 m distance Average home 50 Quiet library 40Quiet bedroom at night 30 Background in TV studio 20

2.2.4 Screening, Diagnosis, and Monitoring Systems

Polysomnography (PSG) is a conventional system for diagnosis andmonitoring of cardio-pulmonary disorders, and typically involves expertclinical staff to apply the system. PSG typically involves the placementof 15 to 20 contact sensors on a patient in order to record variousbodily signals such as electroencephalography (EEG), electrocardiography(ECG), electrooculograpy (EOG), electromyography (EMG), etc. PSG forsleep disordered breathing has involved two nights of observation of apatient in a clinic, one night of pure diagnosis and a second night oftitration of treatment parameters by a clinician. PSG is thereforeexpensive and inconvenient. In particular it is unsuitable for homescreening/diagnosis/monitoring of sleep disordered breathing.

Screening and diagnosis generally describe the identification of acondition from its signs and symptoms. Screening typically gives atrue/false result indicating whether or not a patient's SDB is severeenough to warrant further investigation, while diagnosis may result inclinically actionable information. Screening and diagnosis tend to beone-off processes, whereas monitoring the progress of a condition cancontinue indefinitely. Some screening/diagnosis systems are suitableonly for screening/diagnosis, whereas some may also be used formonitoring.

Clinical experts may be able to screen, diagnose, or monitor patientsadequately based on visual observation of PSG signals. However, thereare circumstances where a clinical expert may not be available, or aclinical expert may not be affordable. Different clinical experts maydisagree on a patient's condition. In addition, a given clinical expertmay apply a different standard at different times.

3 BRIEF SUMMARY OF THE TECHNOLOGY

The present technology is directed towards providing medical devicesused in the screening, diagnosis, monitoring, amelioration, treatment,or prevention of respiratory disorders having one or more of improvedcomfort, cost, efficacy, ease of use and manufacturability.

A first aspect of the present technology relates to apparatus used inthe screening, diagnosis, monitoring, amelioration, treatment orprevention of a respiratory disorder.

Another aspect of the present technology relates to methods used in thescreening, diagnosis, monitoring, amelioration, treatment or preventionof a respiratory disorder.

An aspect of certain forms of the present technology is to providemethods and/or apparatus that improve the compliance of patients withrespiratory therapy.

One form of the present technology is a patient interface for sealeddelivery of a flow of air at a continuously positive pressure withrespect to ambient air pressure to an entrance to a patient's airwaysincluding at least entrance of a patient's nares, wherein the patientinterface is configured to maintain a therapy pressure in a range ofabout 4 cmH₂O to about 30 cmH₂O above ambient air pressure in use,throughout a patient's respiratory cycle, while the patient is sleeping,to ameliorate sleep disordered breathing; said patient interfacecomprising:

-   -   a plenum chamber at least partially forming a cavity        pressurisable to a therapeutic pressure of at least 6 cmH₂O        above ambient air pressure, said plenum chamber including a        plenum chamber inlet port sized and structured to receive a flow        of air at the therapeutic pressure for breathing by a patient;        and    -   a seal-forming structure.

One form of the present technology comprises a textile seal-formingstructure with a bridge portion between a first hole and a second hole,the bridge portion is crimped so as to be held in greater tension than aremainder of the textile membrane.

Another aspect of one form of the present technology is a seal-formingstructure having a textile membrane coupled to a flexible supportstructure in a relaxed state, and a bridge portion of the textilemembrane is crimped so as to be held in greater tension than a remainderof the textile membrane.

Another aspect of the present technology is a patient interface forsealed delivery of a flow of air at a continuously positive pressurewith respect to ambient air pressure to an entrance to a patient'sairways including at least entrance of a patient's nares, wherein thepatient interface is configured to maintain a therapy pressure in arange of about 4 cmH2O to about 30 cmH2O above ambient air pressure inuse, throughout a patient's respiratory cycle, while the patient issleeping, to ameliorate sleep disordered breathing; said patientinterface comprising:

-   -   a plenum chamber at least partially forming a cavity        pressurisable to a therapeutic pressure of at least 6 cmH2O        above ambient air pressure, said plenum chamber including a        plenum chamber inlet port sized and structured to receive a flow        of air at the therapeutic pressure for breathing by a patient;        and    -   a seal-forming structure having:        -   a textile membrane constructed and arranged to form a            pressure-assisted seal with a region of the patient's face            surrounding an entrance to the patient's airways inferior to            a nasal bridge region of the patient's face, said textile            membrane having a portion, the seal-forming structure            constructed and arranged to maintain said therapeutic            pressure in the cavity throughout the patient's respiratory            cycle in use,    -   wherein:        -   the textile membrane is held in a relaxed state, and        -   the portion is held in greater tension than a remainder of            the textile membrane, e.g., selectively tensioned.

In some aspects, the textile membrane has at least one hole or two holesformed such that the flow of air at said therapeutic pressure isdelivered to at least an entrance to the patient's airways.

In some aspects, the portion is tensioned via various techniques,including crimping at one or more portions of the textile membrane,e.g., a central portion and/or a bridge portion. Instead of or inaddition to the central or bridge portion, one or more other portions ofthe textile membrane may be tensioned, e.g., crimping or othertechniques. The textile membrane may be supported by a flexible supportthat may be subject to selective tensioning, as an alternative or inaddition to selective tensioning of one or more portions of the textilemembrane.

Another aspect of the present technology is a patient interface forsealed delivery of a flow of air at a continuously positive pressurewith respect to ambient air pressure to an entrance to a patient'sairways including at least entrance of a patient's nares, wherein thepatient interface is configured to maintain a therapy pressure in arange of about 4 cmH₂O to about 30 cmH₂O above ambient air pressure inuse, throughout a patient's respiratory cycle, while the patient issleeping, to ameliorate sleep disordered breathing; said patientinterface comprising:

-   -   a plenum chamber at least partially forming a cavity        pressurisable to a therapeutic pressure of at least 6 cmH₂O        above ambient air pressure, said plenum chamber including a        plenum chamber inlet port sized and structured to receive a flow        of air at the therapeutic pressure for breathing by a patient;        and    -   a seal-forming structure having:        -   a textile membrane constructed and arranged to form a            pressure-assisted seal with a region of the patient's face            surrounding an entrance to the patient's airways inferior to            a nasal bridge region of the patient's face, said textile            membrane having at least one hole such that the flow of air            at said therapeutic pressure is delivered to at least an            entrance to the patient's nares, the seal-forming structure            constructed and arranged to maintain said therapeutic            pressure in the cavity throughout the patient's respiratory            cycle in use,    -   wherein:        -   the textile membrane includes a first portion held in a            relaxed state and a second portion held in a taut state, the            taut state of the second portion configured to allow the            seal-forming structure to include a three-dimensional shape            having multiple curvatures.

In some aspects, a) an area of the first portion is greater than an areaof the second portion; b) the at least one hole includes a first holeand a second hole, each configured to be positioned adjacent one of thepatient's nares in use, and wherein a bridge portion is disposed betweenthe first hole and the second hole; c) the bridge portion is the secondportion and is held in a taut state; d) the bridge portion is crimped soas to be held in greater tension than the first portion of the textilemembrane; e) the bridge portion includes a first section and a secondsection, the first section being substantially flat and configured tocontact the patient in use, and the second section extending into theplenum chamber; f) the bridge portion is crimped using ultrasonicwelding and/or an adhesive; and/or g) ultrasonic welding and/oradhesives are applied to the second section.

In some aspects a) the seal-forming structure further includes aflexible support structure for holding the textile membrane in thethree-dimensional shape; b) the seal-forming structure includes a singlewall, and wherein an end of the flexible support structure contacts thetextile membrane; c) the seal-forming structure includes a pair ofwalls, wherein the flexible support structure includes a free end, andthe textile membrane is coupled to the flexible support structure distalto the free end, and wherein the free end is spaced apart from thetextile membrane so that the textile membrane is arranged radiallyoutside of the free end; d) the flexible support structure is coupled tothe textile membrane using injection molding; and/or e) the bridgeportion is a locating spigot after being crimped.

In some aspects a) the textile membrane includes a first curvature abouta first axis intersecting the first hole and the second hole, andwherein before being crimped, the bridge portion includes a bridgecurvature about the first axis in an opposite direction from a remainderof the textile membrane; b) a second axis extends transverse to thefirst axis and along the bridge portion, the textile membrane includinga secondary curvature about the second axis; c) the secondary curvaturehas one of a domed region and a saddle region, and the first curvaturehas the other of a domed region and a saddle region; d) the secondarycurvature is configured to contact the patient's subnasale, in use; e) athird axis extends transverse to the second axis and skewed with respectto the first axis, the textile membrane including a tertiary curvatureabout the third axis; f) the tertiary curvature is configured to contactthe patient's lip superior, in use; g) a fourth axis extends transverseto the second axis and to the third axis, and parallel to the firstaxis, the textile membrane including a quaternary curvature about thefourth axis; h) the quaternary curvature includes a variable radius ofcurvature; and/or i) the quaternary curvature extends into the primarycurvature proximate to an edge of the textile membrane.

In some aspects a) a portion of the first hole distal to the bridgeportion is movable between a first position and a second position; b)the first position is a natural state, and the textile membrane moves tothe second position as a result of an external force; c) the portion ofthe first hole extends into the plenum chamber in the second position;d) the first hole includes a substantially tear-drop shape in the secondposition; e) in the second position, the first hole is configured tocontact a periphery of the entrance to one of the patient's naresproximate to an alar rim; and/or f) a portion of the second hole distalto the bridge portion is movable between the first position and thesecond position.

In some aspects a) the textile membrane includes a textile layer and asilicone layer coupled to the textile layer, the silicone layer havingimpermeable properties; b) the silicone layer is approximately 0.5 mmthick.; c) the silicone layer is disposed within the cavity and isconfigured to not touch the patient's skin, in use; and/or d) thesilicone layer has a low durometer characteristic, and the textilemembrane includes a high stretch capability when coupled to the flexiblesupport structure.

In some aspects a) a length of the bridge portion is directly related toa size of the first hole and to a size of the second hole; b) thetextile membrane is configured to be curved about at least twonon-parallel axes as a result of taut state of the second portion inorder to form the three-dimensional shape; c) the textile membraneincludes a multi-layered textile material and silicone layer coupled tothe multi-layered textile material; d) the multi-layered textilematerial includes a first layer, a second layer, and a third layer, thesilicone layer contacting only the first layer, and wherein the thirdlayer is configured to contact the patient's face, in use; e) the firstlayer and the third layer are constructed from nylon, and wherein thesecond layer is constructed from spandex; f) the textile membrane isapproximately 0.35 mm to approximately 0.45 mm thick; and/or g) thepatient's nose and lip superior are configured to contact only thetextile membrane, in use.

Another aspect of the present technology is a patient interface forsealed delivery of a flow of air at a continuously positive pressurewith respect to ambient air pressure to an entrance to a patient'sairways including at least entrance of a patient's nares, wherein thepatient interface is configured to maintain a therapy pressure in arange of about 4 cmH2O to about 30 cmH2O above ambient air pressure inuse, throughout a patient's respiratory cycle, while the patient issleeping, to ameliorate sleep disordered breathing; said patientinterface comprising:

-   -   a plenum chamber at least partially forming a cavity        pressurisable to a therapeutic pressure of at least 6 cmH2O        above ambient air pressure, said plenum chamber including a        plenum chamber inlet port sized and structured to receive a flow        of air at the therapeutic pressure for breathing by a patient;        and    -   a seal-forming structure having:        -   a textile membrane constructed and arranged to form a            pressure-assisted seal with a region of the patient's face            surrounding an entrance to the patient's airways inferior to            a nasal bridge region of the patient's face, said textile            membrane having a first hole and a second hole and a bridge            portion disposed between the first hole and the second hole,            the first hole and the second hole formed therein such that            the flow of air at said therapeutic pressure is delivered to            at least an entrance to the patient's nares, the            seal-forming structure constructed and arranged to maintain            said therapeutic pressure in the cavity throughout the            patient's respiratory cycle in use, and        -   a flexible support structure for holding the textile            membrane in a predefined shape;    -   wherein:        -   the textile membrane is coupled to the flexible support            structure in a relaxed state, and        -   the bridge portion is crimped so as to be held in greater            tension than a remainder of the textile membrane.

Another aspect of the present technology is a patient interface forsealed delivery of a flow of air at a continuously positive pressurewith respect to ambient air pressure to an entrance of a patient's naresand to an entrance of the patient's mouth, wherein the patient interfaceis configured to maintain a therapy pressure in a range of about 4 cmH2Oto about 30 cmH2O above ambient air pressure in use, throughout apatient's respiratory cycle, while the patient is sleeping, toameliorate sleep disordered breathing; said patient interfacecomprising:

-   -   a plenum chamber at least partially forming a cavity        pressurisable to a therapeutic pressure of at least 6 cmH2O        above ambient air pressure, said plenum chamber including a        plenum chamber inlet port sized and structured to receive a flow        of air at the therapeutic pressure for breathing by a patient;        and    -   a seal-forming structure comprising a textile membrane        constructed and arranged to form a pressure-assisted seal with a        region of the patient's face surrounding the entrance to the        patient's nares and the entrance to the patient's mouth, the        seal-forming structure comprising:        -   a nasal portion configured to at least partially surround            the entrance to the patient's nares, and        -   an oral portion configured to at least partially surround            the entrance to the patient's mouth,        -   wherein said textile membrane having at least one hole such            that the flow of air at said therapeutic pressure is            delivered to at least the entrance to the patient's nares            and/or to the entrance of the patient's mouth, the            seal-forming structure constructed and arranged to maintain            said therapeutic pressure in the cavity throughout the            patient's respiratory cycle in use,        -   wherein the textile membrane includes a first portion held            in a relaxed state and a second portion held in a taut            state, the taut state of the second portion configured to            allow the seal-forming structure to include a            three-dimensional shape having multiple curvatures.

In some aspects a) the at least one hole includes a naris openingconfigured to be positioned adjacent to the patient's nares, and an oralportion hole configured to be positioned adjacent the patient's mouth inuse; b) a bridge portion extends across the naris opening and dividesthe naris opening into a first hole and a second hole, each of the firsthole and the second hole configured to be positioned adjacent to one ofthe patients nares in use; c) the bridge portion is the second portionand is held in a taut state; and/or d) the bridge portion is crimpedusing ultrasonic welding and/or an adhesive.

In some aspects a) the first portion is at least partially comprised ofthe oral portion; b) the first portion includes the oral portion and asection of the nasal portion; c) the seal-forming structure furtherincludes a flexible support structure for holding the textile membranein the three-dimensional shape; d) the flexible support structureincludes at least one support rib that engages the oral portion withinthe cavity of the plenum chamber; e) the flexible support structurefurther comprises a secondary rib disposed within the cavity, thesupport rib extending between the secondary rib and the oral portion; f)the textile membrane of the seal-forming structure is curved about atleast two non-parallel axes as a result of taut state of the secondportion in order to form the three-dimensional shape; g) the oralportion is curved about the at least two non-parallel axes; and/or h)the textile membrane includes a textile layer and a silicone layercoupled to the textile layer, the silicone layer having impermeableproperties. In some aspects a) the seal-forming structure is constructedfrom a textile membrane having a first sub-section and a secondsub-section that is spaced apart from the first sub-section; b) theseal-forming structure further comprises a flexible support portionconstructed from a material other than the textile membrane, theflexible support portion disposed between the first sub-section and thesecond sub-section; c) the second sub-section is positioned superior tothe first sub-section in use; d) the second sub-section is disposed atleast partially between ends of the first sub-section; e) the at leastone hole includes a naris opening configured to be positioned adjacentto the patient's nares, and an oral portion hole configured to bepositioned adjacent the patient's mouth, wherein, the first sub-sectioncompletely forms a perimeter of the oral portion hole; and the secondsub-section completely forms a perimeter of the naris opening; f) the atleast one hole includes a naris opening configured to be positionedadjacent to the patient's nares, and an oral portion hole configured tobe positioned adjacent the patient's mouth, wherein, a perimeter of thenaris opening is completely formed by the second sub-section; and aperimeter of the oral portion hole is at least partially formed by acombination of the first sub-section the second sub-section; g) thefirst sub-section forms at least part of the oral portion and includesan annular shape; and/or h) the second sub-section forms at least partof the oral portion and includes a U-shape.

In some aspects a) a single, continuous piece of the textile membrane isused to construct the oral portion and the nasal portion; b) thepatient's nose and lip superior are configured to contact only thetextile membrane, in use; and/or c) foam inserts coupled to theseal-forming structure and configured to contact the patient's nasal alain use.

In some aspects, the textile membrane is configured to include be curvedabout at least two non-parallel axes as a result of the bridge portionbeing crimped.

In some aspects, the bridge portion is crimped using ultrasonic weldingand/or an adhesive.

In some aspects, a length of the bridge portion is directly related to asize of the first hole and to a size of the second hole.

In some aspects, the bridge portion includes a first section and asecond section, the first section being substantially flat andconfigured to contact the patient in use, and the second sectionextending into the plenum chamber.

In some aspects, ultrasonic welding and/or adhesives are applied to thesecond section.

In some aspects, the seal-forming structure includes a single wall, andwherein an end of the flexible support structure contacts the textilemembrane.

In some aspects, the seal-forming structure includes a pair of walls,wherein the flexible support structure includes a free end, and thetextile membrane is coupled to the flexible support structure distal tothe free end, and wherein the free end is spaced apart from the textilemembrane so that the textile membrane is arranged radially outside ofthe free end.

In some aspects, the flexible support structure is coupled to thetextile membrane using injection molding.

In some aspects, the bridge portion is a locating spigot after beingcrimped.

In some aspects, the textile membrane includes a textile layer and asilicone layer coupled to the textile layer, the silicone layer havingimpermeable properties.

In some aspects, the silicone layer is approximately 0.5 mm thick.

In some aspects, the textile membrane includes a multi-layered textilematerial and silicone layer coupled to the multi-layered textilematerial.

In some aspects, the multi-layered textile material includes a firstlayer, a second layer, and a third layer, the silicone layer contactingonly the first layer, and the third layer configured to contact thepatient's face, in use.

In some aspects, the first layer and the third layer are constructedfrom nylon, and wherein the second layer is constructed from spandex.

In some aspects, the silicone layer is disposed within the cavity and isconfigured to not touch the patient's skin, in use.

In some aspects, the silicone layer has a low durometer characteristic,and the textile membrane includes a high stretch capability when coupledto the flexible support structure.

In some aspects, the textile membrane is approximately 0.35 mm toapproximately 0.45 mm thick.

In some aspects, the textile membrane includes a first curvature about afirst axis intersecting the first opening and the second opening, andwherein before being crimped, the bridge portion includes a bridgecurvature about the first axis in an opposite direction from a remainderof the textile membrane.

In some aspects, a second axis extends transverse to the first axis andalong the bridge portion, the textile membrane including a secondarycurvature about the second axis.

In some aspects, the secondary curvature has an opposite concavity thanthe first curvature.

In some aspects, the secondary curvature is configured to contact thepatient's subnasale, in use.

In some aspects, a third axis extends transverse to the second axis andskewed with respect to the first axis, the textile membrane including atertiary curvature about the third axis.

In some aspects, the tertiary curvature is configured to contact thepatient's lip superior, in use.

In some aspects, a fourth axis extends transverse to the second axis andto the third axis, and parallel to the first axis, the textile membraneincluding a quaternary curvature about the fourth axis.

In some aspects, the quaternary curvature includes a variable radius ofcurvature.

In some aspects, the quaternary curvature extends into the primarycurvature proximate to an edge of the textile membrane.

In some aspects, a portion of the first hole distal to the bridgeportion is movable between a first position and a second position.

In some aspects, the first position is a natural state, and the textilemembrane moves to the second position as a result of an external force.

In some aspects, the portion of the first hole extends into the plenumchamber in the second position.

In some aspects, the first hole includes a substantially tear-drop shapein the second position.

In some aspects, in the second position, the first hole is configured tocontact a periphery of the entrance to one of the patient's naresproximate to an alar rim.

In some aspects, a portion of the second hole distal to the bridgeportion is movable between the first position and the second position.

In some aspects, the patient's nose and lip superior are configured tocontact only the textile membrane, in use.

In some aspects, the patient interface is a nasal cushion, nasal cradle,oronasal cushion, ultra-compact full-face mask, or full-face mask.

In another aspect of the present invention, a patient interface forsealed delivery of a flow of air at a continuously positive pressurewith respect to ambient air pressure to an entrance to a patient'sairways including at least entrance of a patient's nares, wherein thepatient interface is configured to maintain a therapy pressure in arange of about 4 cmH2O to about 30 cmH2O above ambient air pressure inuse, throughout a patient's respiratory cycle, while the patient issleeping, to ameliorate sleep disordered breathing; said patientinterface comprising:

-   -   a plenum chamber at least partially forming a cavity        pressurisable to a therapeutic pressure of at least 6 cmH2O        above ambient air pressure, said plenum chamber including a        plenum chamber inlet port sized and structured to receive a flow        of air at the therapeutic pressure for breathing by a patient;        and    -   a seal-forming structure having a textile membrane constructed        and arranged to form a pressure-assisted seal with a region of        the patient's face surrounding an entrance to the patient's        airways inferior to a nasal bridge region of the patient's face,        said textile membrane having a first hole and a second hole and        a bridge portion disposed between the first hole and the second        hole, the first hole and the second hole formed therein such        that the flow of air at said therapeutic pressure is delivered        to at least an entrance to the patient's nares, the seal-forming        structure constructed and arranged to maintain said therapeutic        pressure in the cavity throughout the patient's respiratory        cycle in use,    -   wherein:        -   the seal-forming structure includes a flexible support            structure to hold the textile membrane in a predefined            curved shape, the textile membrane includes a first            curvature about a first axis and a second curvature about a            second axis generally transverse to the first axis, the            first axis configured to be generally transverse to a            sagittal plane of the patient's head so that the first            curvature includes a vertex in a posterior direction so that            the first curvature passes around the nasolabial sulcus of            the patient's nose, and the second axis configured to be            generally parallel with the sagittal plane so that the            second curvature includes a vertex in an inferior direction            so that the second curvature is a saddle region and has a            generally a positive curvature with respect to the patient's            lip superior in use,        -   the bridge portion has a third curvature opposite of the            first curvature, the third curvature of the bridge portion            limiting creasing along the surface of the textile membrane,        -   the textile membrane is coupled to the flexible support            structure in a relaxed state,        -   in use, the textile membrane is configured to press against            the patient's face such that the patient's nose is not            received in the cavity, and        -   the textile membrane is attached to the flexible support            structure along an outer perimeter of the textile membrane            such that textile membrane extends radially inwardly beyond            the support structure.

In some aspects, the bridge portion is crimped in order to maintain thethird curvature and limit flipping to the first curvature.

In some aspects, the bridge portion is crimped using ultrasonic weldingand/or an adhesive.

In some aspects, the textile membrane is substantially impermeable toair.

In some aspects, the textile membrane includes a textile layer and asilicone layer coupled to the textile layer, the silicone layer havingimpermeable properties.

In some aspects, the silicone layer is approximately 0.5 mm thick.

In some aspects, the silicone layer is disposed within the cavity and isconfigured to not touch the patient's skin, in use.

In some aspects, the silicone layer has a low durometer characteristic,and the textile layer includes a high stretch capability when coupled tothe support structure.

In some aspects, the textile membrane is approximately 0.35 mm toapproximately 0.45 mm thick.

In some aspects, the seal-forming structure includes a single wall, andwherein an end of the flexible support structure contacts the textilemembrane.

In some aspects, the seal-forming includes a pair of walls, wherein theflexible support structure includes a free end, and the textile membraneis coupled to the flexible support structure distal to the free end, andwherein the free end is spaced apart from the textile membrane so thatthe textile membrane is arranged radially outside of the free end.

In some aspects, the first hole includes a first arched portion, thefirst arched portion having generally the first curvature, and the firstarched portion is configured to be positioned within a first naris ofthe patient.

In some aspects, the first arched portion is configured to flip fromhaving generally the first curvature to having generally the thirdcurvature after being positioned within the first naris of the patient,the arched portion configured to wrap around a periphery of an entranceto the first naris.

In some aspects, the second hole includes a second arched portion, thesecond arched portion having generally the first curvature, and thesecond arched portion configured to be positioned within a second narisof the patient.

In some aspects, the first hole includes a substantially circular shape,and is configured to include a substantially tear-drop shape aftercontacting the patient's face.

In some aspects, the textile membrane is configured to contact only thepatient's lip superior, subnasale, and pronasale, in use.

In some aspects, the flexible support is coupled to the textile membraneusing injection molding.

In some aspects, the textile membrane includes a fourth curvature abouta fourth axis, the fourth curvature being generally a saddle region witha positive curvature with respect to the patient's subnasale in use, andthe fourth axis being generally transverse to the first axis and to thesecond axis.

In some aspects, an area influenced by the second curvature is formed bya generally rectangular region encompassing the first hole and thesecond hole, the generally rectangular region having a generallytangential relationship with respect to the first hole and to the secondhole, wherein the generally tangential relationship limits creasing inthe textile membrane.

In another aspect of the present technology, a patient interface forsealed delivery of a flow of air at a continuously positive pressurewith respect to ambient air pressure to an entrance to a patient'sairways including at least entrance of a patient's nares, wherein thepatient interface is configured to maintain a therapy pressure in arange of about 4 cmH2O to about 30 cmH2O above ambient air pressure inuse, throughout a patient's respiratory cycle, while the patient issleeping, to ameliorate sleep disordered breathing; said patientinterface comprising:

-   -   a plenum chamber at least partially forming a cavity        pressurisable to a therapeutic pressure of at least 6 cmH2O        above ambient air pressure, said plenum chamber including a        plenum chamber inlet port sized and structured to receive a flow        of air at the therapeutic pressure for breathing by a patient;        and    -   a seal-forming structure having a textile membrane constructed        and arranged to form a pressure-assisted seal with a region of        the patient's face surrounding an entrance to the patient's        airways inferior to a nasal bridge region of the patient's face,        said textile membrane having a first hole and a second hole and        a bridge portion disposed between the first hole and the second        hole, the first hole and the second hole formed therein such        that the flow of air at said therapeutic pressure is delivered        to at least an entrance to the patient's nares, the seal-forming        structure constructed and arranged to maintain said therapeutic        pressure in the cavity throughout the patient's respiratory        cycle in use,    -   wherein:        -   the seal-forming structure includes a flexible support            structure to hold the textile membrane in a predefined            curved shape, the textile membrane includes a first            curvature about a first axis and a second curvature about a            second axis generally transverse to the first axis, the            first axis is configured to be generally transverse to a            sagittal plane of the patient's head so that the first            curvature includes a vertex in a posterior direction so that            the first curvature is generally a negative dome curvature            with respect to the patient's lip superior in use, and the            second axis is configured to be generally parallel with the            sagittal plane so that the second curvature includes a            vertex in an inferior direction so that the second curvature            is generally a saddle region and a positive curvature with            respect to the patient's pronasale in use,        -   the bridge portion has a third curvature opposite of the            first curvature, the third curvature of the bridge portion            limiting creasing along the surface of the textile membrane,    -   the textile membrane is coupled to the flexible support        structure in a relaxed state,    -   in use, the textile membrane is configured to press against the        patient's face such that the patient's nose is not received in        the cavity, and    -   the textile membrane is attached to the flexible support        structure along an outer perimeter of the textile membrane such        that textile membrane extends radially inwardly beyond the        support structure.

In some aspects, the textile membrane includes a fourth curvature abouta fourth axis configured to be generally parallel to the first axis sothat the fourth curvature includes a vertex in the posterior directionso that the fourth curvature passes around the nasolabial sulcus of thepatient's nose.

In some aspects, the bridge portion is crimped in order to maintain thethird curvature and limit flipping to the first curvature.

In some aspects, the bridge portion is crimped using ultrasonic weldingand/or an adhesive.

In some aspects, the textile membrane is substantially impermeable toair.

In some aspects, the textile membrane includes a textile layer and asilicone layer coupled to the textile layer, the silicone layer havingimpermeable properties.

In some aspects, the silicone layer is approximately 0.5 mm thick.

In some aspects, the silicone layer is disposed within the cavity and isconfigured to not touch the patient's skin, in use.

In some aspects, the silicone layer has a low durometer characteristic,and the textile layer includes a high stretch capability when coupled tothe support structure.

In some aspects, the textile membrane is approximately 0.35 mm toapproximately 0.45 mm thick.

In some aspects, the seal-forming structure includes a single wall, andwherein an end of the flexible support structure contacts the textilemembrane.

In some aspects, the seal-forming includes a pair of walls, wherein theflexible support structure includes a free end, and the textile membraneis coupled to the flexible support structure distal to the free end, andwherein the free end is spaced apart from the textile membrane so thatthe textile membrane is arranged radially outside of the free end.

In some aspects, the first hole includes a first arched portion, thefirst arched portion having generally the first curvature, and the firstarched portion is configured to be positioned within a first naris ofthe patient.

In another aspect of the present technology, a seal-forming structurehas:

-   -   a textile membrane constructed and arranged to form a        pressure-assisted seal with a region of the patient's face        surrounding an entrance to the patient's airways inferior to a        nasal bridge region of the patient's face, said textile membrane        having a first hole and a second hole and a bridge portion        disposed between the first hole and the second hole, the first        hole and the second hole formed therein such that the flow of        air at said therapeutic pressure is delivered to at least an        entrance to the patient's nares, the seal-forming structure        constructed and arranged to maintain said therapeutic pressure        in the cavity throughout the patient's respiratory cycle in use,        and    -   a flexible support structure for holding the textile membrane in        a predefined shape;    -   wherein:    -   the textile membrane is coupled to the flexible support        structure in a relaxed state, and    -   the bridge portion is crimped so as to be held in greater        tension than a remainder of the textile membrane.

Another aspect of the present technology is a patient interface forsealed delivery of a flow of air at a continuously positive pressurewith respect to ambient air pressure to an entrance to a patient'sairways including at least entrance of a patient's nares, wherein thepatient interface is configured to maintain a therapy pressure in arange of about 4 cmH2O to about 30 cmH2O above ambient air pressure inuse, throughout a patient's respiratory cycle, while the patient issleeping, to ameliorate sleep disordered breathing; said patientinterface comprising:

-   -   a plenum chamber at least partially forming a cavity        pressurisable to a therapeutic pressure of at least 6 cmH2O        above ambient air pressure, said plenum chamber including a        plenum chamber inlet port sized and structured to receive a flow        of air at the therapeutic pressure for breathing by a patient;        and    -   a seal-forming structure having:        -   a textile membrane constructed and arranged to form a            pressure-assisted seal with a region of the patient's face            surrounding an entrance to the patient's airways inferior to            a nasal bridge region of the patient's face, said textile            membrane having a portion, the seal-forming structure            constructed and arranged to maintain said therapeutic            pressure in the cavity throughout the patient's respiratory            cycle in use,    -   wherein the textile membrane is held in a taut state.

One form of the present technology comprises a textile seal-formingstructure with a bridge portion between a first hole and a second hole,the entire textile seal-forming structure being held in a taut state.

Another aspect of one form of the present technology is a seal-formingstructure having a textile membrane coupled to a flexible supportstructure in a taut state, and a bridge portion of the textile membraneis substantially flat as a result of the tension.

Another aspect of one form of the present technology is a seal-formingstructure having a textile membrane coupled to a flexible supportstructure in a taut state prior to use, the textile membrane having asubstantially flat surface in at least one direction in the taut stateprior to use.

In some aspects, the textile membrane is tensioned via varioustechniques, including without crimping at one or more portions of thetextile membrane, e.g., a central portion and/or a bridge portion. Thecentral portion and/or a bridge portion may be taut and substantiallyflat prior to use by a patient. The textile membrane may be supported bya flexible support and may be stretched, or otherwise tensioned, priorto connecting to flexible support.

Another aspect of one form of the present technology is a patientinterface that is moulded or otherwise constructed with a perimetershape which is complementary to that of an intended wearer.

An aspect of one form of the present technology is a method ofmanufacturing apparatus.

An aspect of certain forms of the present technology is a medical devicethat is easy to use, e.g. by a person who does not have medicaltraining, by a person who has limited dexterity, vision or by a personwith limited experience in using this type of medical device.

An aspect of one form of the present technology is a portable RPT devicethat may be carried by a person, e.g., around the home of the person.

An aspect of one form of the present technology is a patient interfacethat may be washed in a home of a patient, e.g., in soapy water, withoutrequiring specialised cleaning equipment. An aspect of one form of thepresent technology is a humidifier tank that may be washed in a home ofa patient, e.g., in soapy water, without requiring specialised cleaningequipment.

The methods, systems, devices and apparatus described may be implementedso as to improve the functionality of a processor, such as a processorof a specific purpose computer, respiratory monitor and/or a respiratorytherapy apparatus. Moreover, the described methods, systems, devices andapparatus can provide improvements in the technological field ofautomated management, monitoring and/or treatment of respiratoryconditions, including, for example, sleep disordered breathing.

Of course, portions of the aspects may form sub-aspects of the presenttechnology. Also, various ones of the sub-aspects and/or aspects may becombined in various manners and also constitute additional aspects orsub-aspects of the present technology.

Other features of the technology will be apparent from consideration ofthe information contained in the following detailed description,abstract, drawings and claims.

4 BRIEF DESCRIPTION OF THE DRAWINGS

The present technology is illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawings, in whichlike reference numerals refer to similar elements including:

4.1 RESPIRATORY THERAPY SYSTEMS

FIG. 1A shows a system including a patient 1000 wearing a patientinterface 3000, in the form of nasal pillows, receiving a supply of airat positive pressure from an RPT device 4000. Air from the RPT device4000 is humidified in a humidifier 5000, and passes along an air circuit4170 to the patient 1000. A bed partner 1100 is also shown. The patientis sleeping in a supine sleeping position.

FIG. 1B shows a system including a patient 1000 wearing a patientinterface 3000, in the form of a nasal mask, receiving a supply of airat positive pressure from an RPT device 4000. Air from the RPT device ishumidified in a humidifier 5000, and passes along an air circuit 4170 tothe patient 1000.

FIG. 1C shows a system including a patient 1000 wearing a patientinterface 3000, in the form of a full-face mask, receiving a supply ofair at positive pressure from an RPT device 4000. Air from the RPTdevice is humidified in a humidifier 5000, and passes along an aircircuit 4170 to the patient 1000. The patient is sleeping in a sidesleeping position.

4.2 RESPIRATORY SYSTEM AND FACIAL ANATOMY

FIG. 2A shows an overview of a human respiratory system including thenasal and oral cavities, the larynx, vocal folds, oesophagus, trachea,bronchus, lung, alveolar sacs, heart and diaphragm.

FIG. 2B shows a view of a human upper airway including the nasal cavity,nasal bone, lateral nasal cartilage, greater alar cartilage, nostril,lip superior, lip inferior, larynx, hard palate, soft palate,oropharynx, tongue, epiglottis, vocal folds, oesophagus and trachea.

FIG. 2C is a front view of a face with several features of surfaceanatomy identified including the lip superior, upper vermilion, lowervermilion, lip inferior, mouth width, endocanthion, a nasal ala,nasolabial sulcus and cheilion. Also indicated are the directionssuperior, inferior, radially inward and radially outward.

FIG. 2D is a side view of a head with several features of surfaceanatomy identified including glabella, sellion, pronasale, subnasale,lip superior, lip inferior, supramenton, nasal ridge, alar crest point,otobasion superior and otobasion inferior. Also indicated are thedirections superior & inferior, and anterior & posterior.

FIG. 2E is a further side view of a head. The approximate locations ofthe Frankfort horizontal and nasolabial angle are indicated. The coronalplane is also indicated.

FIG. 2F shows a base view of a nose with several features identifiedincluding naso-labial sulcus, lip inferior, upper Vermilion, naris,subnasale, columella, pronasale, the major axis of a naris and themidsagittal plane.

FIG. 2G shows a side view of the superficial features of a nose.

FIG. 2H shows subcutaneal structures of the nose, including lateralcartilage, septum cartilage, greater alar cartilage, lesser alarcartilage, sesamoid cartilage, nasal bone, epidermis, adipose tissue,frontal process of the maxilla and fibrofatty tissue.

FIG. 2I shows a medial dissection of a nose, approximately severalmillimeters from the midsagittal plane, amongst other things showing theseptum cartilage and medial crus of greater alar cartilage.

FIG. 2J shows a front view of the bones of a skull including thefrontal, nasal and zygomatic bones. Nasal concha are indicated, as arethe maxilla, and mandible.

FIG. 2K shows a lateral view of a skull with the outline of the surfaceof a head, as well as several muscles. The following bones are shown:frontal, sphenoid, nasal, zygomatic, maxilla, mandible, parietal,temporal and occipital. The mental protuberance is indicated. Thefollowing muscles are shown: digastricus, masseter, sternocleidomastoidand trapezius.

FIG. 2L shows an anterolateral view of a nose.

4.3 PATIENT INTERFACE

FIG. 3A shows a patient interface in the form of a nasal mask inaccordance with one form of the present technology.

FIG. 3B shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a positive sign, and a relatively large magnitude whencompared to the magnitude of the curvature shown in FIG. 3C.

FIG. 3C shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a positive sign, and a relatively small magnitude whencompared to the magnitude of the curvature shown in FIG. 3B.

FIG. 3D shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a value of zero.

FIG. 3E shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a negative sign, and a relatively small magnitude whencompared to the magnitude of the curvature shown in FIG. 3F.

FIG. 3F shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a negative sign, and a relatively large magnitude whencompared to the magnitude of the curvature shown in FIG. 3E.

FIG. 3G shows a cushion for a mask that includes two pillows. Anexterior surface of the cushion is indicated. An edge of the surface isindicated. Dome and saddle regions are indicated.

FIG. 3H shows a cushion for a mask. An exterior surface of the cushionis indicated. An edge of the surface is indicated. A path on the surfacebetween points A and B is indicated. A straight line distance between Aand B is indicated. Two saddle regions and a dome region are indicated.

FIG. 3I shows the surface of a structure, with a one dimensional hole inthe surface. The illustrated plane curve forms the boundary of a onedimensional hole.

FIG. 3J shows a cross-section through the structure of FIG. 3I. Theillustrated surface bounds a two dimensional hole in the structure ofFIG. 3I.

FIG. 3K shows a perspective view of the structure of FIG. 3I, includingthe two dimensional hole and the one dimensional hole. Also shown is thesurface that bounds a two dimensional hole in the structure of FIG. 3I.

FIG. 3L shows a mask having an inflatable bladder as a cushion.

FIG. 3M shows a cross-section through the mask of FIG. 3L, and shows theinterior surface of the bladder. The interior surface bounds the twodimensional hole in the mask.

FIG. 3N shows a further cross-section through the mask of FIG. 3L. Theinterior surface is also indicated.

FIG. 3O illustrates a left-hand rule.

FIG. 3P illustrates a right-hand rule.

FIG. 3Q shows a left ear, including the left ear helix.

FIG. 3R shows a right ear, including the right ear helix.

FIG. 3S shows a right-hand helix.

FIG. 3T shows a view of a mask, including the sign of the torsion of thespace curve defined by the edge of the sealing membrane in differentregions of the mask.

FIG. 3U shows a view of a plenum chamber 3200 showing a sagittal planeand a mid-contact plane.

FIG. 3V shows a view of a posterior of the plenum chamber of FIG. 3U.The direction of the view is normal to the mid-contact plane. Thesagittal plane in FIG. 3V bisects the plenum chamber into left-hand andright-hand sides.

FIG. 3W shows a cross-section through the plenum chamber of FIG. 3V, thecross-section being taken at the sagittal plane shown in FIG. 3V. A‘mid-contact’ plane is shown. The mid-contact plane is perpendicular tothe sagittal plane. The orientation of the mid-contact plane correspondsto the orientation of a chord 3210 which lies on the sagittal plane andjust touches the cushion of the plenum chamber at two points on thesagittal plane: a superior point 3220 and an inferior point 3230.Depending on the geometry of the cushion in this region, the mid-contactplane may be a tangent at both the superior and inferior points.

FIG. 3X shows the plenum chamber 3200 of FIG. 3U in position for use ona face. The sagittal plane of the plenum chamber 3200 generallycoincides with the midsagittal plane of the face when the plenum chamberis in position for use. The mid-contact plane corresponds generally tothe ‘plane of the face’ when the plenum chamber is in position for use.In FIG. 3X the plenum chamber 3200 is that of a nasal mask, and thesuperior point 3220 sits approximately on the sellion, while theinferior point 3230 sits on the lip superior.

4.4 RPT DEVICE

FIG. 4A shows an RPT device in accordance with one form of the presenttechnology.

FIG. 4B is a schematic diagram of the pneumatic path of an RPT device inaccordance with one form of the present technology. The directions ofupstream and downstream are indicated with reference to the blower andthe patient interface. The blower is defined to be upstream of thepatient interface and the patient interface is defined to be downstreamof the blower, regardless of the actual flow direction at any particularmoment. Items which are located within the pneumatic path between theblower and the patient interface are downstream of the blower andupstream of the patient interface.

4.5 BREATHING WAVEFORMS

FIG. 5 shows a model typical breath waveform of a person while sleeping.

4.6 PATIENT INTERFACE ACCORDING TO THE PRESENT TECHNOLOGY

FIG. 6 is a perspective view of a patient interface according to anexample of the present technology worn by a patient.

FIG. 7 is a perspective view of a patient interface according to anotherexample of the present technology worn by a patient.

FIG. 8 is a cross-sectional view of the positioning and stabilisingstructure along the line 8-8 in FIG. 7 .

FIG. 9 is an enlarged view of a portion of the positioning andstabilising structure of FIG. 8 .

FIG. 10 is an enlarged view of a portion of the positioning andstabilising structure of FIG. 8 .

FIG. 11 is a front view of the cushion assembly of FIG. 6 positioned ona patient's face.

FIG. 12 is a front perspective view of a cushion assembly according toan example of the present technology.

FIG. 13 is a front view of the cushion assembly of FIG. 12 .

FIG. 14 is a top perspective view of the cushion assembly of FIG. 12 .

FIG. 15 is a top view of the cushion assembly of FIG. 12 .

FIG. 16 is a cross-sectional view along the line 16-16 in FIG. 12 .

FIG. 17 is a cross-sectional view along the line 17-17 in FIG. 12 .

FIG. 18 is an enlarged detail taken from FIG. 16 .

FIGS. 19-21 are front perspective views of cushion assemblies havinggrip pads disposed on the textile membrane according examples of thepresent technology.

FIG. 22 is a perspective view of a patient interface according toanother example of the present technology.

FIG. 23 is a perspective view of the patient interface of FIG. 22 wornby a patient.

FIG. 24 is a side view of the patient interface of FIG. 23 .

FIG. 25 is a front perspective view of the patient interface of FIG. 23.

FIG. 26 is a front view of a cushion assembly of a patient interface inaccordance to an example of the present technology.

FIG. 27 is a top view of the cushion assembly of FIG. 26 .

FIG. 28 is a bottom view of the cushion assembly of FIG. 26 .

FIG. 29 is a front perspective view of the cushion assembly of FIG. 26 .

FIG. 30 is a rear perspective view of the cushion assembly of FIG. 26 .

FIG. 31 is a side perspective view of the cushion assembly of FIG. 26 .

FIG. 32 is a front perspective view of the cushion assembly of FIG. 26showing an interior portion of the cushion assembly.

FIG. 33 is a front view of the cushion assembly of FIG. 26 showing aninterior portion of the cushion assembly.

FIG. 33-1 is a rear perspective view of a cushion assembly according toan example of the present technology.

FIG. 33-2 is a rear perspective view of a cushion assembly according toan example of the present technology.

FIG. 33-3 is a rear perspective view of a cushion assembly according toan example of the present technology, where a sealing portion isconstructed from a single piece of textile material.

FIG. 33-4 is a rear perspective view of the cushion assembly of FIG.33-3 , illustrating a more positively domed curvature of the sealingportion at a location configured to contact the patient's lip superior.

FIG. 33-5 is a top view of the cushion assembly of FIG. 33-4 .

FIG. 33-6 is a side perspective view of the cushion assembly of FIG.33-3 , illustrating support ribs.

FIG. 33-7 is a side perspective view of the cushion assembly of FIG.33-3 , illustrating larger support ribs as compared to FIG. 33-6 .

FIG. 33-8 is a rear perspective view of the cushion assembly of FIG.33-3 having a thicker corner of nose region in order to provide anarrower space to receive a patient's nose.

FIG. 33-9 is a top view of the cushion assembly of FIG. 33-8 .

FIG. 33-10 is a front view of the cushion assembly of FIG. 33-3 ,illustrating raising a conduit connector portion as compared to thepatient interface of FIG. 24 .

FIG. 33-11 is a rear perspective view of the cushion assembly of FIG.33-3 , illustrating foam inserts configured to contact a patient'scorner of nose region.

FIG. 34 is a rear view of a cushion assembly used with the patientinterface of FIG. 22 .

FIG. 35 is a front view of the cushion assembly of FIG. 34 .

FIG. 36 is a cross-sectional view of the cushion assembly of FIG. 34 ,viewed along line 36-36.

FIGS. 37-39 are front perspective views of cushion assemblies havinggrip pads disposed on the textile membrane according examples of thepresent technology.

FIG. 40 is a schematic illustration of a process of providing an airimpermeable layer to a textile material according to an example of thepresent technology.

FIG. 40-1 is a schematic illustration a process of providing an airimpermeable layer to a textile material according to another example ofthe present technology.

FIG. 41 is a schematic illustration depicting a patient's face beingpresented to a textile membrane in light tension prior to use.

FIG. 42 is a schematic illustration showing a resulting force exerted bythe textile membrane on the patient's face due to tensile stress in thetextile membrane.

FIG. 43 is a schematic illustration of tension forces exerted on thesealing portion of a cushion assembly according to an example of thepresent technology.

FIG. 44 is a schematic illustration of a force exerted by the textilemembrane on the patient's face due to air pressure within the cavityformed by the cushion assembly.

FIGS. 45 and 46 depict a knitting process.

FIG. 47 illustrates a warp knitted textile according to an example ofthe present technology.

FIG. 48 illustrates a weft knitted textile according to an example ofthe present technology.

FIG. 49 is a perspective view of a textile material folded about a firstaxis.

FIG. 50 is a perspective view of the textile material of FIG. 49 ,folded about the first axis and a second axis. The second axis isnon-parallel to the first axis, and a fold about the second axis createsa crease and/or wrinkle in the textile material.

FIG. 51 is a perspective view of a textile material for use as aseal-forming structure. The textile material is folded about three,non-parallel axes and treated in order to limit the creation of creasesand/or wrinkles.

FIG. 52 is a perspective view of the textile material of FIG. 49 , witha pair of openings cut into the material, and a bridge portionpositioned between the two openings.

FIG. 53 is a perspective view of the textile material of FIG. 52 ,illustrating the bridge portion flipped about a second axis, parallel tothe first axis.

FIG. 54 is a perspective view of the textile material of FIG. 53 ,illustrating the bridge portion under tension via a crimping process.

FIG. 55 is a perspective view of the textile material of FIG. 53 ,folded about non-parallel axes. Folding the bridge portion limits thecreation of creases and/or wrinkles in the textile material.

FIG. 56 is a detail view of the textile material of FIG. 55 ,illustrating the curvatures about different axes.

FIG. 57 is a detail view of a textile material illustrating acircumference of the opening, which may be changed depending on thelength of the bridge portion that is crimped.

FIG. 58 is a cross-sectional view of a cushion assembly formed with thetextile material of FIG. 54 . A flexible support structure contacts thetextile material in order to form a single wall.

FIG. 59 is a cross-sectional view of a cushion assembly formed with thetextile material of FIG. 54 . A portion of a flexible support structureis spaced apart from the textile material in order to form two walls.

FIG. 60 is a perspective view of a cushion assembly formed with thetextile material of FIG. 54 . The textile material includes an archedportion partially surrounding the opening.

FIG. 61 is a perspective view of the cushion assembly of FIG. 60 ,illustrating the arched portion flipped inwardly so that the openingincludes a substantially tear-dropped shape.

5. DETAILED DESCRIPTION OF EXAMPLES OF THE TECHNOLOGY

Before the present technology is described in further detail, it is tobe understood that the technology is not limited to the particularexamples described herein, which may vary. It is also to be understoodthat the terminology used in this disclosure is for the purpose ofdescribing only the particular examples discussed herein, and is notintended to be limiting.

The following description is provided in relation to various exampleswhich may share one or more common characteristics and/or features. Itis to be understood that one or more features of any one example may becombinable with one or more features of another example or otherexamples. In addition, any single feature or combination of features inany of the examples may constitute a further example.

5.1 THERAPY

In one form, the present technology comprises a method for treating arespiratory disorder comprising applying positive pressure to theentrance of the airways of a patient 1000.

In certain examples of the present technology, a supply of air atpositive pressure is provided to the nasal passages of the patient viaone or both nares.

In certain examples of the present technology, mouth breathing islimited, restricted or prevented.

5.2 RESPIRATORY THERAPY SYSTEMS

In one form, the present technology comprises a respiratory therapysystem for treating a respiratory disorder. The respiratory therapysystem may comprise an RPT device 4000 for supplying a flow of air tothe patient 1000 via an air circuit 4170 and a patient interface 3000.

5.3 PATIENT INTERFACE

A non-invasive patient interface 3000 in accordance with one aspect ofthe present technology comprises the following functional aspects: aseal-forming structure 3100, a plenum chamber 3200, a positioning andstabilising structure 3300, a vent 3400, one form of connection port3600 for connection to air circuit 4170, and a forehead support 3700. Insome forms a functional aspect may be provided by one or more physicalcomponents. In some forms, one physical component may provide one ormore functional aspects. In use the seal-forming structure 3100 isarranged to surround an entrance to the airways of the patient so as tomaintain positive pressure at the entrance(s) to the airways of thepatient 1000. The sealed patient interface 3000 is therefore suitablefor delivery of positive pressure therapy.

If a patient interface is unable to comfortably deliver a minimum levelof positive pressure to the airways, the patient interface may beunsuitable for respiratory pressure therapy.

The patient interface 3000 in accordance with one form of the presenttechnology is constructed and arranged to be able to provide a supply ofair at a positive pressure of at least 6 cmH2O with respect to ambient.

The patient interface 3000 in accordance with one form of the presenttechnology is constructed and arranged to be able to provide a supply ofair at a positive pressure of at least 10 cmH2O with respect to ambient.

The patient interface 3000 in accordance with one form of the presenttechnology is constructed and arranged to be able to provide a supply ofair at a positive pressure of at least 20 cmH2O with respect to ambient.

5.3.1 Seal-Forming Structure

In one form of the present technology, a seal-forming structure 3100provides a target seal-forming region, and may additionally provide acushioning function. The target seal-forming region is a region on theseal-forming structure 3100 where sealing may occur. The region wheresealing actually occurs the actual sealing surface may change within agiven treatment session, from day to day, and from patient to patient,depending on a range of factors including for example, where the patientinterface was placed on the face, tension in the positioning andstabilising structure and the shape of a patient's face.

In one form the target seal-forming region is located on an outsidesurface of the seal-forming structure 3100.

In certain forms of the present technology, the seal-forming structure3100 is constructed from a biocompatible material, e.g. silicone rubber.

A seal-forming structure 3100 in accordance with the present technologymay be constructed from a soft, flexible, resilient material such assilicone.

In some forms, such as those illustrated in FIGS. 6 to 39 , theseal-forming structure 3100, 6100, 9100 has a sealing portion thatcomprises a textile material, which may cover the entirety or a portionof the seal-forming structure 3100, 6100, 9100. In some forms, thetextile may comprise a material formed of a network of fibres and beadapted such that it is air impermeable. For example, the textile mayhave an air impermeable film on at least one surface thereof therebyforming a textile membrane or textile sealing portion.

In some forms, the textile membrane may be constructed so as to stretchelastically in at least one dimension. For example, when a textilemembrane is constructed from a network of fibres, the textile membranemay be capable of elongating in a longitudinal warp direction and/or alateral weft direction across the textile membrane. In some forms, atextile membrane is constructed so as to elongate elastically to anextent greater than that achievable by conventional siliconeseal-forming structures.

In some forms, the textile membrane is constructed so as to besubstantially inelastic in at least one dimension. For example, when atextile membrane is constructed from a woven textile material, thetextile membrane may be capable of substantially resisting elongation ineither, or both of, a longitudinal warp direction or a lateral weftdirection across the textile membrane.

The textile membrane may comprise a single layer or a plurality oflayers. In forms where a plurality of layers are utilised, theindividual layers can be formed using the same material, or a variety ofdifferent materials each with unique material properties.

In some forms, the textile membrane may comprise at least one layer thatexhibits substantially air-impermeable characteristics, whilemaintaining the material characteristics necessary for providing comfortand minimal pressure points to the patient. For example, as illustratedin FIG. 40 , in some forms a textile membrane may comprise an airimpermeable material 10131 (e.g., a silicone layer) formed on onesurface of a textile material 10133. The air impermeable material 10131can in some forms be laminated onto the textile material 10133. The airimpermeable material 10131 and textile material 10133 can, in someforms, be selected such that the resulting textile membrane 10135 canexhibit a predetermined overall elasticity, or a resistance toelasticity, as required. For example, the addition of the airimpermeable material 10131 (or membrane layer) may add elasticity (orstretchiness) to the textile material 10133 such that the resultingtextile membrane 10135 has increased stretchability. The air impermeablematerial 10131 may also have a low durometer characteristic so as not toimpede on the elasticity of the textile material 10133. In other words,the textile membrane 10135 will have substantially the same elasticityas the textile material 10133 does alone, so that the addition of theair impermeable material 10131 will not substantially reduce theelasticity (or stretchiness) of the textile material 10133.

The air impermeable material 10131 may have a thickness substantiallyless than the thickness of the textile material 10133. This may assistin maintaining a substantially light weight textile membrane 10135,because the relatively small thickness of air impermeable material 10131may not significantly add weight to the textile material 10133. Thepatient interface with a textile membrane 10135 that includes the airimpermeable material 10131 may not feel noticeably heavier than apatient interface that includes only the textile material 10133.

In some examples, the thickness of the textile membrane 10135 is betweenapproximately 0.25 mm and approximately 0.55 mm. In some examples, thethickness of the textile membrane 10135 is between approximately 0.30 mmand approximately 0.50 mm. In some examples, the thickness of thetextile membrane 10135 is between approximately 0.35 mm andapproximately 0.45 mm. In some examples, the thickness of the textilemembrane 10135 is approximately 0.40 mm.

In some examples, the thickness of the air impermeable membrane 10131 isbetween approximately 0.01 mm and approximately 0.10 mm. In someexamples, the thickness of the air impermeable membrane 10131 is betweenapproximately 0.02 mm and approximately 0.08 mm. In some examples, thethickness of the air impermeable membrane 10131 is between approximately0.03 mm and approximately 0.07 mm. In some examples, the thickness ofthe air impermeable membrane 10131 is between approximately 0.04 mm andapproximately 0.06 mm. In some examples, the thickness of the airimpermeable membrane 10131 is approximately 0.05 mm.

In some forms, the textile material 10133 may be formed as a multiplelayered textile. In other words, multiple pieces of textiles may becombined together in order to form the overall textile material 10133.As shown in FIG. 40-1 , the textile material 10133 may be constructedfrom three layers (although any number of layers may be used). A secondlayer 10133 b of the textile material 10133 may be sandwiched between afirst layer 10133 a and a third layer 10133 c. In the illustratedexample, the second layer 10133 b (i.e., the middle layer) isconstructed from spandex, and the first and third layers 10133 a, 10133c (i.e., inner and outer layers) are constructed from nylon. However,other materials may be used without departing from the scope and spiritof these forms. Additionally, the first and third layers 10133 a, 10133c may be formed from different materials (i.e., non-identicalmaterials).

In some forms, the overall composition of the textile material 10133 maybe at least 50% nylon and at most 50% spandex. In some forms, theoverall composition of the textile material 10133 may be betweenapproximately 60% to approximately 90% nylon and between approximately10% to approximately 40% spandex. In some forms, the overall compositionof the textile material 10133 may be between approximately 70% toapproximately 85% nylon and between approximately 15% to approximately30% spandex. In some forms, the overall composition of the textilematerial 10133 may be approximately 82% nylon and approximately 18%spandex (e.g., JCD4018 produced by WeiMei Fabrics Limited).

In some forms, the layered structure may provide the textile material10133 with a spongy feel. In other words, the textile material 10133 maybe compliant and may deform as it comes in contact with the patient'sface. Specifically, the thickness of the textile material 10133 may becapable of decreasing when a force is applied, and returning to itsoriginal shape when the force is removed. Thus, the textile material10133 may act like a sponge because it is capable of at least partiallyabsorbing an applied force. Specifically, the spandex layer 10133 b ofthe textile material 10133 may provide the spongy feel (e.g., because ofits elastic properties). The spongy feel of the textile material 10133may help to improve comfort against a patient's skin (e.g., because thetextile material 10133 is able to conform to a variety of facialcontours). The spongy feel of the textile material 10133 may also assistin improving the seal against the patient's face. Particularly, thetextile material 10133 may be able to deform into crevices on thepatient's face (e.g., the region between the nasal ala and thenasolabial sulcus) as a result of an applied force (e.g., via apositioning and stabilizing structure 3300), but will not crease andform locations where air could leak out. This may assist the patient inestablishing a seal between their skin and the textile membrane 10135,without needing the textile membrane 10135 to contact the exact samelocation (e.g., which may make donning the seal-forming structure 3100easier). This may also allow the seal-forming structure 3100, 6100, 9100to move and/or shift while it is worn without creating a leak, becausethe spongy properties assist in maintaining the necessary contactagainst the patient's skin.

In some forms, the textile material 10133 is coated (e.g., laminated)with an air impermeable layer 10131 (e.g., liquid silicone rubber) inorder to form a textile membrane 10135 with impermeable properties. Inthe illustrated example, the air impermeable layer 10131 is applied to asingle side of the textile material 10133. In other words, the airimpermeable layer 10131 may be applied to the first layer 10133 a, butnot to the second or third layers 10133 b, 10133 c. When the textilemembrane 10135 is constructed as a seal-forming structure 3100, 6100,9100, the first layer 10133 a is configured to be positioned within acavity 3101, 6001, 9001, so that the third layer 10133 c is configuredto face and contact the patient.

In one form, the textile material 10133 is formed from a fine knittextile. Specifically, the first and third layers 10133 a, 10133 c areconstructed with a fine knit. This may be a textile that is less thanapproximately 100 denier. This may be a textile that is less thanapproximately 50 denier. This may be a textile that is approximatelydenier. The fine knit of the textile, particularly in the third layer10133 c, provides a smooth feeling to the patient's skin, which maypromote patient compliance (e.g., because of added comfort). The fineknit of the textile may also prevent seepage of the air impermeablelayer 10131 through the textile layer 10133 (e.g., during amanufacturing process). For example, the fine knit of the first layer10133 a may limit all seepage, or may allow some seepage, but maysubstantially limit seepage into the other layers 10133 b, 10133 c. Inother words, the first layer 10133 a acts as a barrier and substantiallylimits the air impermeable layer 10131 from contacting and/or coatingthe second layer 10133 b or the third layer 10133 c. Since the firstlayer 10133 a does not contact the patient, some seepage may bepermitted since the relative stiffness of the first layer 10133 a isless important to patient comfort than that of the third layer 10133 c(i.e., which directly contacts the patient's skin). Thus, the spandexmay not lose its elasticity as a result of contacting the airimpermeable layer 10131. Additionally, the third layer 10133 c may notlose its smooth texture as a result of becoming impregnated with the airimpermeable layer 10131. And since only one surface of the textilematerial 10133 needs to be coated with the air impermeable material10131 (i.e., for the textile membrane 10135 to have impermeableproperties), an impermeable membrane 10135 may be constructed that doesnot substantially limit patient comfort.

In some embodiments, coating the textile material 10133 with the airimpermeable material does not substantially affect the materialproperties of the textile membrane 10133. For example, since the airimpermeable material 10131 is substantially blocked from reaching thesecond layer 10133 b, the spandex that forms the second layer 10133 bdoes not experience a substantial decrease in elasticity. This enablesthe textile membrane 10135 as a whole to continue to stretch as a resultof an applied force. Additionally, the third layer 10133 c may lose itsability to drape, and instead become stiff, if impregnated with the airimpermeable layer 10131. This may reduce the ability for the third layer10133 c to seal against a patient's face. Thus, in addition to comfort,blocking the air impermeable layer 10131 from the third layer 10133 ckeeps the third layer 10133 c substantially loose, and capable ofsealing against a patient's face.

In some embodiments, the air impermeable layer 10131 includes athickness T_(I1) of no more than approximately 500 microns. In someembodiments, the air impermeable layer 10131 includes a thickness T_(I1)of between approximately 4 microns to approximately 400 microns. In someembodiments, the air impermeable layer 10131 includes a thickness T_(I1)of between approximately 8 microns to approximately 300 microns. In someembodiments, the air impermeable layer 10131 includes a thickness T_(I1)of between approximately 12 microns to approximately 200 microns. Insome embodiments, the air impermeable layer 10131 includes a thicknessT_(I1) of between approximately 16 microns to approximately 100 microns.In some embodiments, the air impermeable layer 10131 includes athickness T_(I1) of between approximately 20 microns to approximately 70microns. In some embodiments, the air impermeable layer 10131 includes athickness T_(I1) of approximately 40 microns.

In some embodiments, the actual thickness TI₂ of the air impermeablelayer 10131 in the textile membrane 10135 may be less than the thicknessT_(I1) of the air impermeable layer 10131 prior to being coated to thetextile material 10133 (although this is not always the case). In otherwords, if the air impermeable material 10131 seeps into the first layer10133 a, then the thickness T_(I1) of the air impermeable layer 10131partially overlaps with the thickness of the first layer 10133 a, sothat a thickness T_(I2) measured from an outer surface (i.e., surfacefacing the cavity) of the first layer 10133 a to an exposed surface(i.e., surface facing the cavity) of the air impermeable layer 10131 isless than the total thickness T_(I1) of the air impermeable layer 10131.

Even if the thickness T_(I2) of the air impermeable layer 10131 is less(e.g., because of seepage), the density remains substantially the same.In some embodiments, the air impermeable layer 10131 includes a densityof no more than approximately 500 grams per meter squared (GSM). In someembodiments, the air impermeable layer 10131 includes a density ofbetween approximately 5 GSM to approximately 400 GSM. In someembodiments, the air impermeable layer 10131 includes a density ofbetween approximately 50 GSM to approximately 300 GSM. In someembodiments, the air impermeable layer 10131 includes a density ofbetween approximately 100 GSM to approximately 200 GSM. In someembodiments, the air impermeable layer 10131 includes a density ofbetween approximately 110 GSM to approximately 130 GSM. In someembodiments, the air impermeable layer 10131 includes a density ofapproximately 120 GSM.

The textile membrane 10135 includes a variety of benefits as a result ofmaintaining separation between the air impermeable layer 10131 and thesecond and third layers 10133 b (i.e., the middle layer), 10133 c (i.e.,the patient contacting layer). As described above, the materialproperties of the textile material 10133 is not substantially sacrificedin order to achieve an impermeable membrane 10135. The third layer inparticular 10133 maintains a smooth surface texture in order to providecomfort to the patient, and the second layer 10133 b does notsubstantially lose its elasticity. The first layer 10133 a, the thirdlayer 10133 c, and the air impermeable layer 10131 may all also haveelastic properties, so that they can stretch with the second layer 10133b. In particular, the air impermeable layer may have a low durometer(e.g., between approximately 20 to approximately 40), which may provideit with more stretchiness (e.g., it does not substantially limit theability of the textile material 10133 to stretch) as compared to an airimpermeable layer 10131 with a greater durometer.

In other examples, the textile membrane 10135 in constructed entirelyfrom a textile material 10133. The textile material 10133 may includeair impermeable threads that impart impermeability onto the textilemembrane 10135. The additional layer of air impermeable material 10131may not be needed, which may allow the textile membrane 10135 to bethinner (i.e., just the thickness of the textile material). The airimpermeable threads may have similar elastic properties to non-airimpermeable threads, so that the textile membrane 10135 with the airimpermeable threads does not lose stretchiness.

In some forms, the textile membrane 10135 can exhibit a low springconstant (i.e. high compliance) in both warp and weft. In such forms,unlike conventional designs where a fixed cushion may cause the skin ofa patient's face 1300 to distort in order to form an effective seal, thetextile material 10133 and/or the resulting textile membrane 10135 mayhave a material spring constant and spring length such that the textilemembrane 10135 is more compliant than the patient's skin that engagesthe textile membrane 10135. This may advantageously improve the comfortof the mask, and reduce the formation of localized pressure “hot spots,”or locations likely to result in irritation because of contact with theseal-forming structure 3100, 6100, 9100.

In some forms, the surface of the textile material 10133 that contactsthe patient's face 1300 can have low friction characteristics. This mayadvantageously improve the comfort of the surface texture of the textilemembrane 10135 and reduce friction relative to the patient's face 1300.The textile material 10133 may have a surface (e.g., herringbone) thatmay have a first coefficient of friction in a first direction that isdifferent (e.g., greater or less) than a coefficient of friction in asecond direction. In contrast, higher friction textiles may cause thetextile membrane 10135 to grip or rub against contacted regions of thepatient's face, in use. Such rubbing or gripping may cause the textilemembrane 10135 to be distorted or deformed thereby reducing theeffectiveness of the seal and allowing air to leak undesirably from thedevice.

In certain forms of the present technology, a system is providedcomprising more than one a seal-forming structure 3100, each beingconfigured to correspond to a different size and/or shape range. Forexample the system may comprise one form of a seal-forming structure3100 suitable for a large sized head, but not a small sized head andanother suitable for a small sized head, but not a large sized head.

It is noted that although the specification may refer (e.g., byreference character) to a particular illustrated example or a feature ofa particular illustrated example (e.g., seal-forming structure 3100),such discussion may be applicable to other examples and/or features(e.g., seal-forming structure 6100, 9100).

5.3.1.1 Sealing Mechanisms

In one form, the seal-forming structure includes a sealing flangeutilizing a pressure assisted sealing mechanism. In use, the sealingflange can readily respond to a system positive pressure in the interiorof the plenum chamber 3200 acting on its underside to urge it into tightsealing engagement with the face. The pressure assisted mechanism mayact in conjunction with elastic tension in the positioning andstabilising structure.

In one form, the seal-forming structure 3100 comprises a sealing flangeand a support flange. The sealing flange comprises a relatively thinmember with a thickness of less than about 1 mm, for example about 0.25mm to about 0.45 mm, which extends around the perimeter of the plenumchamber 3200. Support flange may be relatively thicker than the sealingflange. The support flange is disposed between the sealing flange andthe marginal edge of the plenum chamber 3200, and extends at least partof the way around the perimeter. The support flange is or includes aspring-like element and functions to support the sealing flange frombuckling in use.

In one form, a textile membrane 3130 (e.g., comprising nylon, polyester,nylon and polyester mix, microfiber or polyurethane) is used as theface-contacting portion of the seal-forming structure 3100 for the CPAPmask. The textile membrane 3130 may be bio-compliant, and may provide asubstantially smooth and comfortable surface for the patient, which mayimprove patient compliance (e.g., because they are not wearing anirritating device). The textile membrane 3130 may have properties suchthat it is capable of elongating in at least one dimension. Prior touse, the textile membrane 3130 can be either permanently attached (e.g.,molded) or attached as a removable module to a support structure (e.g.,a flexible support structure 3120).

In one form, the textile membrane 3130 can be formed as a complexthree-dimensional pre-determined shape such that it is untensioned(e.g., loose, slack and/or unwrinkled) prior to and/or during use, butthere are no substantial leak causing wrinkles. The textile membrane3130 may include one or more curvatures when attached to a supportstructure 3120, which may assist in conforming to various contours of apatient's face. Before the patient's face (e.g., a nose) approaches anddepresses the textile membrane 3130, the textile membrane 3130 isadapted to form a constant surface without interruptions such ascreases, folds or wrinkles. In some forms, this can be accomplished bymolding the textile membrane 3130 such that it is substantially free ofany leak causing wrinkles. This can be advantageous in ensuring that thetextile membrane 3130 forms a smooth and continuous seal on and aroundthe patient's face. This may provide improved respiratory pressuretherapy by reducing occurrences of folded or wrinkled sections of theseal-forming structure 3100 through which treatment air may leak.

In some forms, regions of the textile membrane 3130 can be pre-tensioned(e.g., under tension before being contacted by the patient's face) andlightly stretched while other regions of the textile membrane 3130 canremain slack. In other words, the entire textile membrane 3130 may notbe pre-tensioned. Having a textile membrane 3130 with various tensionsmay advantageously improve the seal efficiency while reducing pressure(i.e. “hot spots”) on regions where the facial anthropometrics protrudea greater distance into or towards the cavity 3101. In some examples,the side of nose region (e.g., lateral side 3250 and/or corner regions3252) may remain untensioned and/or slack prior to use, in order toprovide additional material to accommodate the facial contours of thesesensitive facial areas. In some examples, a bridge portion 3104 mayextend between two naris openings 3102, and may be tensioned, as shownfor example in FIG. 12-21 . The tension applied to the bridge portion3104 may allow for one possible way for the textile membrane 3130 toinclude complex shapes (e.g., multiple curvatures) in order to bettercontour to a patient's face, while including significantly less tensionthroughout the remainder of the textile membrane 3130 (e.g., as comparedto the bridge portion 3104). Having a wide expanse of untensionedtextile membrane 3130 may be more comfortable in some arrangements, asthe untensioned textile may apply less pressure on the patient's face.

By retaining the textile membrane 3130 in an unwrinkled statecontinuously prior to and during use, the textile membrane 3130 canconform to the patient's facial profile while minimizing wrinkles and/orblow-out of the seal-forming structure. In some forms, this may alsoimprove seal performance by maximising the contact area of the textilemembrane 3130 on the patient's face. In some forms, this may alsoimprove the performance of the CPAP device when it is impacted byexternal lateral or longitudinal forces (e.g., tube drag).

In some forms, when the plenum chamber 3200 is pulled a small distanceaway from the patient's face, the applied loading of the air pressurefrom within the plenum chamber 3200 can assist the textile membrane 3130in retaining an effective seal. The applied loading of the air pressurecan be sufficient so as to elastically stretch the textile membrane 3130in at least one dimension such that it forms a “hover-craft” likeballoon effect over the anthropometric contours of a patient's face 1300thus retaining an effective seal thereon.

In some forms, the textile membrane 3130 may be held by a relativelystiffer support structure 3120. In various forms, the support structure3120 can be formed from for example, any of silicone, PU foam, PU solidmaterial or another suitable materials. While the support structure 3120is stiffer than the textile membrane 3130, it may still be described asflexible, and may be capable of flexing or bending as a result of anapplied tension. In some forms, the support structure 3120 may berelatively less stiff than a shell or frame of the plenum chamber 3200(e.g., that is formed from hard plastic). In other forms, the plenumchamber 3200 does not include a shell or frame, and is constructedentirely from the textile membrane 3130 and the support structure 3120.

In some forms, a magnitude of the tensile stress can vary across thetextile membrane 3130 of the seal-forming structure 3100 as required.The bridge portion 3104 may be held in tension, and the remainder of thetextile membrane 3130 may be understood to be unstretched, as comparedto the bridge portion 3104. The bridge portion 3104 is illustrated asbeing in a central portion of the textile membrane 3130, however thebridge portion 3104 (or any similar feature where tension is selectivelyapplied), may be at any location throughout the textile membrane 3130.However, different locations on the textile membrane 3130 may includedifferent degrees of tension (i.e., but all less than the bridge portion3104). For example, there may be a region of stress concentrationproximal to one or more holes (e.g., naris openings 3102) in the textilemembrane 3130 through which treatment is administered or in widerstretches of material. In some examples, the region of the textilemembrane 3130 (e.g., outer periphery) directly connected to the supportstructure 3120 may be held in greater tension than the radially innerportions of the textile membrane 3130, except for the bridge portion3104, which may include the highest tension.

In some forms, the seal-forming structure 3100 can utilize a number ofdifferent cushion configurations including a single air assisted textilemembrane 3130, a double air assisted textile membrane 3130, a textilemembrane 3130 with compression support, or a textile membrane 3130 withTPU/TPE/Si support. In some forms, the cushion configuration of theseal-forming structure 3100 may be formed such that it canadvantageously provide a “one-size-fits-most” solution.

In examples, the seal-forming structure 3100 and plenum chamber 3200 canbe applied to nasal cushions, nasal cradles, oronasal cushions,ultra-compact full-face masks, full-face masks and other suitablecushion arrangements.

In some forms, the textile membrane 3130 may be configured to generatean effective seal against the subnasale portion of the patients nosesuch that the textile membrane 3130 does not engage the pronasale, asshown for example in FIG. 23 . In some forms, the textile membrane maybe configured to generate an effective seal across the patient'spronasale (not shown).

In some forms, the air pressure within the cavity 3101 may apply a loadagainst the inside surface of the textile membrane (e.g., an airimpermeable layer 10131) to create further tensile stress such that thetextile membrane 3130 substantially fills the depressed contours of apatient's face 1300 (e.g. around the nasal ala, adjacent to the alarrim, etc.). In some forms, the elasticity of the textile membrane 3130,when combined with the applied load of the internal air pressure, canelastically stretch the textile membrane 3130 such that it forms alarger seal contact area on the patient's face. This may in some formsalso be advantageous in providing a continuous seal, even when the maskis partially displaced from an optimal interface with the patient'sface, as the textile membrane 3130 may partially inflate (i.e. a“hovercraft effect”) due to the counter-force from the internal airpressure.

In some forms, such as illustrated in FIGS. 19-21 and 37-39 , thetextile membrane 3130, 9130 may have one or more grip pads 3150, 9150arranged thereon. In an example, the grip pads 3150, 9150 may beconfigured to be either substantially flat along the patient facingsurface of the textile membrane 3130, 9130. In other examples, the grippads 3150, 9150 may be embossed such that the grip pad 3150, 9150 mayform a bead or rim that protrudes slightly above the surface of thetextile membrane 3130, 9130. In some forms, the grip pads 3150, 9150 mayhave a high coefficient of friction. In some forms, the grip pads 3150,9150 may have a determined shape (e.g., ovular (see FIGS. 19, 21, 37,and 39 ), circular, square, etc.). In some forms, the grip pads 3150,9150 may be elongate (see FIGS. 19 and 37 ). In some forms, the grippads 3150, 9150 may be linear. In some forms, the grip pads 3150, 9150may be arranged in a pattern across the surface of the seal-formingstructure 3100, 9100. In some forms, the grip pads 3150, 9150 may bearranged sporadically across the surface of the seal-forming structure3100, 9100 (see FIGS. 21 and 39 ). In some forms, the grip pads 3150,9150 may be arranged to form a perimeter proximal to the peripheraledges of the textile membrane 3130, 9130 (see FIGS. 19, 20, 37, and 38). In some forms, the grip pads 3150, 9150 that form a perimeter can bein the form of a dotted line (see FIGS. 19 and 37 ). In some forms, thegrip pads 3150, 9150 that form a perimeter can be in the form of a solidline (see FIGS. 20 and 38 ). In some forms, the grip pads 3150, 9150that form a perimeter can be in the form of a plurality of lines, dottedor solid or a combination thereof. In some forms, the grip pads 3150,9150 may assist a textile membrane 3130, 9130 in gripping a patient'sface. In an example, the grip pads 3150, 9150 are formed as a relativelythin layer of silicone applied to the surface of the textile membrane3130, 9130. In any of the above configurations, the grip pads 3150, 9150may provide an additional material (e.g., textile and silicone) thatcontacts the patient's face. While it may not provide the level ofcomfort that an entirely textile surface could provide (e.g., where onlythe textile material of the textile membrane contacts the patient'snose), including grip pads 3150, 9150 on the textile membrane 3130, 9130may provide benefits of helping to ensure that the seal-formingstructure 3100, 9100 remains in a proper position (e.g., in order todeliver therapeutic pressure to a patient). Additionally, having only asmall area covered with silicone (or other gripping material) ascompared to the relatively large area of textile (or being entirelysilicone), may be more comfortable to a patient than an entireseal-forming structure 3100, 9100 formed from silicone (or other similarmaterial).

In some forms, the textile membrane 3130 may be integrated to thesupport structure 3120 by attaching (e.g., molding) an outer edge (e.g.,outer perimeter) of the textile membrane 3130 around a lip of the curvededges (i.e., inner edge) of the support structure 3120. In an example,the textile membrane 3130 is attached so as to provide a front face ofthe seal-forming structure 3100. The textile membrane 3130 also extendsin the anterior direction, so that the textile membrane 3130 curves awayfrom the front face. In other words, the textile membrane 3130 is curvedso as to extend beyond the front face, and provides additional surfacearea of textile material exposed to the patient. This arrangement may beadvantageous because substantially all of the patient's face in contactwith the seal-forming structure 3100 is in contact with the textilemembrane 3130. This may be beneficial in improving patient compliance,because contact with the textile membrane 3130 may be more comfortablefor a patient, and therefore the patient may be more likely to wear apatient interface 3000 that incorporates the textile membrane 3130, thana patient interface 3000 that includes at least some other material(e.g., silicone) in a face contacting region.

In an example, the textile membrane 3130 is attached to the supportstructure 3120 by a specific process (as will be described later) thatmay form the curved portions without creating folds, creases, wrinkles,or buckles in the textile membrane surface 3130. As can be seen, in someexamples, at a transition portion 36, the support structure 3120 and thetextile membrane 3130 may both have a radius of curvature (e.g., thesame or similar radius of curvature) along the curve 35 in a directionfrom the anterior side of the seal-forming structure 3100 to theposterior side of the seal-forming structure (see FIGS. 16-18 ). Thetextile membrane 3130 may have a predefined curvature imparted theretosuch that a portion of the textile membrane 3130 not directly supportedby the support structure 3120 extends along the curve 35 (FIGS. 16-18 ).The textile membrane 3130 may be held in slight tension against thesupport structure 3120, but the textile membrane 3130 not directlysupported by (e.g., not in direct contact with) the support structure3120 may be considered to be substantially slack (e.g., and under lesstension than the bridge portion 3104). This may help create a dome shape(e.g., convex dome) in certain regions (e.g., lateral side 3250 and/orcorner regions 3252) of the textile membrane 3130 which may help thetextile membrane 3130 seal against the contours of the patient's face(e.g., the subnasale region of the patient's face (i.e., the corner ofnose regions, i.e., the region where the ala terminate at the lipsuperior proximate the nasolabial sulcus)), as shown for example in FIG.12 . The dome shape may help prevent creases, wrinkles, folds, andbuckles from forming in the textile membrane 3130 which may help avoidthe creation of leak paths. Also, the dome shape may help the textilemembrane 3130 reach into hard to seal areas of the patient's face, suchas the corner of nose regions. The textile membrane 3130 may have asaddle shape at a medial subnasale region 3260 configured to sealagainst the patient's subnasale thereby matching the saddle shape formedby the patient's nasolabial angle and lip superior, as shown in FIG. 12. Similarly, a pronasale region 3270 may also have a saddle shapeconfigured to seal against the matching profile presented at or belowthe patient's pronasale. The curvature (e.g., magnitude of curvatureand/or radius of curvature) of the textile membrane 3130 in thedirection of the curve 35 may vary in different regions of the cushionassembly along an outer perimeter of the textile membrane 3130. Forexample, as shown in FIG. 16 , the textile membrane 3130 in the medialpronasale region 3270 may have different curvature in the direction ofthe curve 35 than the textile membrane 3130 in the medial subnasaleregion 3260. In an example, the curvature (e.g., magnitude of curvatureand/or radius of curvature) at a lateral side 3250 of the textilemembrane 3130 may be different that the curvature at the medialpronasale region 3270 and/or medial subnasale region 3260.

In some forms, the textile membrane 3130 may be slightly angled orcurved inwardly toward the mask interior (e.g., positive domed curvaturein a left-right direction), as shown for example in FIGS. 12-21 . Insome forms, the textile membrane 3130 may form a dome shape over thesupport structure 3120, as shown for example in FIGS. 26-33 . It isnoted that any of the cushion assemblies 6105, 9105 disclosed herein mayhave the textile membrane 6130, 9130 attached to an outer edge of thesupport structure 6120, 9120 such that the textile membrane 6130, 9130forms part of the portion of the seal-forming structure 6100, 9100 thatextends along the curve 35 from the anterior side of the seal-formingstructure to the posterior face-contacting side as discussed above withreference to FIG. 12 , such that, for example, the textile membrane 6130of cushion assembly 6105 may have more of a dome shape by virtue of anegative curvature from one lateral side to the other lateral side. Inother words, the textile membrane 6130 can be formed with both an inwardcurve and a dome shape, because the textile membrane 6130 is attached tothe support structure 6120 with curvatures in different directionsand/or about different axes. In one example, the majority of the textilemembrane 6130 includes a positive (e.g., inward) curvature that maycradle a portion of the patient's face, and only the peripheries (e.g.,regions proximate to the support structure) are dome shaped (e.g.,include a negative curvature).

In some forms, a central portion of the textile membrane 3130 has asaddle shape. In other words, the peripheries of the textile membrane3130 may be shaped with a negatively domed curvature (e.g., relative tothe patient's face in use), and the central portion includes apositively domed curvature (e.g., about the bridge portion 3104), sothat the central portion (e.g., proximate to the bridge portion 3104)may be considered a minimax point (e.g., relative to the patient's facein use), and thus a saddle.

In some forms where the textile membrane 3130 is not under continuoustension (prior to and/or during use) or is non-elastic, the textilemembrane 3130 may form an improved air-assisted seal on a patient's facethat conforms dynamically to alterations/movement (i.e. “hovercrafteffect”), for example due to the textile membrane 3130 being thinner andhaving a lower structural stiffness than support structure 3120 (e.g.,silicone membrane).

In some forms, the textile membrane 3130 may be supported by a secondaryor tertiary support structure that may act as a cushion support. Acushion support can provide additional flexibility and may be suitablefor use by most patient's faces (one-size-fits-most). The second orthird support layer can be formed using a membrane of a textile, atextile with PU/Si membrane, laminated open cell foam, a laminated PUfoam, PU molding, TPU/TPE or silicone. In some forms, additional supportlayers can themselves be supported by a structural/rigid plastic such asPP/PC/PA/PET or other suitable materials.

In some forms, 3D printing of the textile membrane and/or cushionsupport sections as a “skeleton” can reduce the thickness and as aconsequence, may reduce the weight of the mask.

In some forms, multiple different layers of the mask layers could beprinted with different rigidity, hardness, or thicknesses. For example,“skeleton” sections may be formed using Si, PU Foam, PU solid materialor any suitable plastic material.

In one form, the seal-forming structure may comprise a compressionsealing portion or a gasket sealing portion. In use the compressionsealing portion, or the gasket sealing portion is constructed andarranged to be in compression, e.g. as a result of elastic tension inthe positioning and stabilising structure.

In one form, the seal-forming structure comprises a tension portion. Thetension portion may be located at any number of discrete locationsthroughout the seal-forming structure. In use, the tension portion isheld in tension, e.g. by adjacent regions of the sealing flange.

In one form, the seal-forming structure comprises a region having atacky or adhesive surface.

In certain forms of the present technology, a seal-forming structure maycomprise one or more of a pressure-assisted sealing flange, acompression sealing portion, a gasket sealing portion, a tensionportion, and a portion having a tacky or adhesive surface.

5.3.1.2 Nose Bridge or Nose Ridge Region

In one form, the non-invasive patient interface 3000 comprises aseal-forming structure that forms a seal in use on a nose bridge regionor on a nose-ridge region of the patient's face.

In one form, the seal-forming structure includes a saddle-shaped regionconstructed to form a seal in use on a nose bridge region or on anose-ridge region of the patient's face.

5.3.1.3 Upper Lip Region

In one form, the non-invasive patient interface 3000 comprises aseal-forming structure that forms a seal in use on an upper lip region(that is, the lip superior) of the patient's face.

In one form, the seal-forming structure includes a saddle-shaped regionconstructed to form a seal in use on an upper lip region of thepatient's face.

5.3.1.4 Chin-Region

In one form the non-invasive patient interface 3000 comprises aseal-forming structure that forms a seal in use on a chin-region of thepatient's face.

In one form, the seal-forming structure includes a saddle-shaped regionconstructed to form a seal in use on a chin-region of the patient'sface.

5.3.1.5 Forehead Region

In one form, the seal-forming structure that forms a seal in use on aforehead region of the patient's face. In such a form, the plenumchamber may cover the eyes in use.

5.3.1.6 Nasal Pillows

In one form the seal-forming structure of the non-invasive patientinterface 3000 comprises a pair of nasal puffs, or nasal pillows, eachnasal puff or nasal pillow being constructed and arranged to form a sealwith a respective naris of the nose of a patient.

Nasal pillows in accordance with an aspect of the present technologyinclude: a frusto-cone, at least a portion of which forms a seal on anunderside of the patient's nose, a stalk, a flexible region on theunderside of the frusto-cone and connecting the frusto-cone to thestalk. In addition, the structure to which the nasal pillow of thepresent technology is connected includes a flexible region adjacent thebase of the stalk. The flexible regions can act in concert to facilitatea universal joint structure that is accommodating of relative movementboth displacement and angular of the frusto-cone and the structure towhich the nasal pillow is connected. For example, the frusto-cone may beaxially displaced towards the structure to which the stalk is connected.

5.3.2 Nasal Cushion

Referring to FIGS. 6-21 a patient interface 3000 with a cushion assembly3105 including a seal-forming structure 3100 and a plenum chamber 3200is shown in accordance with a first example of the present technology.

The examples of seal-forming structure 3100 described in the precedingparagraph may be considered nasal cradle cushions and are intended toprovide a flow of pressurised gas to the patient's nares by sealingagainst at least the underside of the patient's nose. The exemplaryseal-forming structure 3100 may engage the patient's face below thebridge of the nose and some examples, depending on the size and shape ofthe patient's nose, may engage the patient's nose below the pronasale.The exemplary seal-forming structure 3100 may also engage the patient'sface at least above the upper vermillion. Thus, the exemplaryseal-forming structure 3100 may seal against the patient's lip superiorin use. Furthermore, the patient's mouth may remain uncovered by theseal-forming structure 3100 of the depicted examples such that thepatient may breathe freely, i.e., directly to atmosphere, withoutinterference from the seal-forming structure 3100. The under-the-nosenasal cradles may be configured such that they do not have an aperturesized to receive the patient's nose within the cavity. Further, a heightof the cushion 3105 from an inferior edge of the textile membrane at amedial subnasale region to a superior edge of the textile membrane 3130at a medial pronasale region may be less than a width of the cushion3105 in a left-right direction from a lateral edge of the textilemembrane 3130 to the other lateral edge of the textile membrane 3130(see e.g., FIG. 12 ).

Examples of a nasal cradle cushion 3105, e.g., the exemplaryseal-forming structures 3100 disclosed herein, may include a superiorsaddle or concave region that has positive curvature across the cushion.Also, a nasal cradle cushion 3105 may be understood to have a singletarget seal forming region or surface, whereas a pillows cushion mayhave two target seal forming regions (one for each naris). Cradlecushions 3105 may also have a posterior wall that contacts the patient'slip superior and an upper, central, surface contacts the underside ofthe patient's nose (e.g., the patient's subnasale and/or columella).These two surfaces on the patient's face may form a nasolabial anglebetween them (see FIG. 2E). A cradle cushion 3105 may be shaped to havea nasolabial angle within the range of 90 degrees to 120 degrees.

Furthermore, the exemplary seal-forming structure 3100 may also beshaped and dimensioned such that no portion of the seal-formingstructure 3100 substantially enters into the patient's nares during use.In other words, a portion of the seal-forming structure 3100 may contactthe alar rim and extend slightly inside in some orientations, but theseal-forming structure 3100 is not substantially sealing within thenasal passages (e.g., as opposed to a nasal pillow style mask).

5.3.2.1 Plenum Chamber

Referring to FIGS. 6-21 , the plenum chamber 3200 has a perimeter thatis shaped to be complementary to the surface contour of the face of anaverage person in the region where a seal will form in use. In use, amarginal edge of the plenum chamber 3200 is positioned in closeproximity to an adjacent surface of the face. Actual contact with theface is provided by the seal-forming structure 3100. The seal-formingstructure 3100 may extend in use about any portion of the perimeter ofthe plenum chamber 3200 (e.g., about the entire perimeter, about amajority of the perimeter, etc.).

In certain forms of the present technology, the plenum chamber 3200 maybe constructed from a flexible material (e.g., silicone) and may beformed as a one-piece structure with the support structure 3120 (e.g.,from any of the materials described herein as suitable for the supportstructure 3120 and/or plenum chamber 3200). In some examples, theseal-forming structure 3100 may be an extension of the plenum chamber3200 or formed as a part of the plenum chamber 3200 such that the plenumchamber 3200 encompasses the seal-forming structure 3100. In such anexample, the support structure 3120 and textile membrane 3130 may beconsidered part of the plenum chamber 3200 (e.g., the seal-formingstructure 3100 at least partially forms the internal volume of theplenum chamber 3200). In some examples, the plenum chamber 3200 may beconstructed from a transparent material (e.g. a transparent silicone).The use of a transparent material can reduce the obtrusiveness of thepatient interface 3000, and help improve compliance with therapy. Theuse of a transparent material can aid a clinician (or patient) inobserving how the patient interface is located and functioning (e.g., toensure a proper seal), and in observing the cleanliness of the patientinterface 3000. A transparent material may allow a clinician or patientto observe a build-up of debris (e.g., dirt, mold, etc.) within theplenum chamber 3200, so that the patient interface 3000 can be cleanedor replaced. This may give the patient a sense of cleanliness whenwearing the patient interface and may assist in ensuring that thepatient is not inhaling harmful materials, both of which may improvepatient compliance. A translucent material may be used instead of or inaddition to a transparent material, and may provide the patient withsimilar benefits. Alternatively, the plenum chamber 3200 is constructedfrom a relatively rigid material (e.g., polycarbonate) as compared tothe seal-forming structure 3100. The rigid material may also beconstructed from a transparent and/or translucent material (e.g., atransparent polycarbonate, etc.), in order to achieve the similarbenefits of flexible transparent material (e.g., to allow forobservation).

In some forms, the seal-forming structure 3100 may include a plenumchamber 3200 connection opening where the seal-forming structure 3100 issealingly joined to the plenum chamber 3200. The seal-forming structure3100 and the plenum chamber 3200 may at least partly form a cavity 3101that is pressurized by the flow of air. In the illustrated example, theseal-forming structure 3100 and the plenum chamber 3200 together formthe cavity 3101. At least one opening (e.g., a pair of nasal openings3102) in the seal-forming structure may allow for fluid communicationbetween the cavity 3101 and the patient's nares. However, the nasalopenings 3102 are not large enough to allow the patient's nose (e.g.,the pronasale) into the cavity 3101.

The connection between the seal-forming structure 3100 and the plenumchamber 3200 at the plenum chamber connection opening 3106 may be apermanent bond. The connection between the seal-forming structure 3100and the plenum chamber 3200 at the plenum chamber connection opening3106 may be a chemical bond. The seal-forming structure 3100 may bejoined to the plenum chamber 3200 at the plenum chamber 3200 connectionopening without a mechanical connection. Alternatively, the seal-formingstructure 3100 may be joined to the plenum chamber 3200 at the plenumchamber connection opening by a mechanical removably detachableconnection.

At each lateral side of the plenum chamber 3200 there may be a plenumchamber lateral end 3202 in the form of a hollow passageway forming aplenum chamber inlet port sized and structured to receive a flow of air.A plenum chamber connector 3204 may also be provided at each lateralside of the plenum chamber 3200 laterally outward of the plenum chamberlateral end 3202. The plenum chamber connectors 3204 may connect torespective ends 3314 of the positioning and stabilising structure 3300.The connection between the plenum chamber connectors 3204 and respectiveends 3314 of the positioning and stabilising structure 3300 may bereleasable at both sides. In other examples, one side may have apermanent connection while the other side has a releasable connection.In still further examples, both connections between the plenum chamberconnectors 3204 and respective ends 3314 of the positioning andstabilising structure 3300 may be permanent.

The plenum chamber lateral ends 3202 may receive the flow of pressurisedgas from the positioning and stabilising structure 3300 (e.g., conduitheadgear). The flow of pressurised gas may then pass through the plenumchamber 3200, then through the seal-forming structure 3100, and into thepatient's airways for inhalation.

The ends 3314 of the positioning and stabilising structure 3300 (e.g.,openings in the respective conduits) may be connected to the plenumchamber lateral ends 3202. Each plenum chamber connector 3204 in theseexamples may include a slot 3209, a chamfered edge 3208, and a notch3206 that may be removably connected to a clip of the positioning andstabilizing structure with a snap-fit.

5.3.2.2 Seal-forming Structure of the Present Technology

The seal-forming structure 3100 may each include a support structure3120 that provides support to a sealing portion 29130 (e.g., a textilemembrane) that creates a seal with the patient's face. The sealingportion 29130 is configured to sealingly engage the patient's face(e.g., when pressurized air is supplied to the plenum chamber 3200).

In one example, the seal-forming structure 3100 may include a supportstructure having at least two regions (e.g., two, three, four, etc.regions) of different thickness (e.g., seal-forming structure 3100comprises support structure 3120 which has a wall structure havinglateral support regions 3122 of an increased thickness with respect toother portions of the wall structure). For example, as shown in FIGS. 58and 59 , some portions 3123 of the support structure 3120 may be thickerthan other portions 3124, 3126 of the support structure 3120. Forexample, the thicker portions 3123 may be adjacent to or connecting tothe plenum chamber 3200 and portions 3124, 3126 may be adjacent to orconnecting to the textile membrane 3130 so as to provide structuralstability at the connection with the plenum chamber 3200 and flexibilityat the interface with the patient. Alternatively, the thicker lateralsupport regions 3122 may be located, for example, at the corner of noseregion of the seal-forming structure (and e.g., may connect directly tothe textile membrane), to ensure adequate sealing in the subalare regionof the patient's face.

Further, in the depicted examples, each textile membrane (e.g., sealingportion) may have two separate naris openings 3102 correspondingrespectively to one of the patient's nares to provide the flow of air toboth of the patient's nares. There may also be a bridge portion 3104positioned between the naris openings 3102. The bridge portion 3104 mayassist in maintaining a desired shape of the textile membrane prior toand/or during use.

The sealing portion 3130 may be less rigid than the support structure3120 and may be constructed from a textile material such as nylon,polyester, nylon and polyester mix, microfiber or polyurethane, forexample, as will be described in more detail later. The sealing portion3130 described in any of the examples of this disclosure may be referredto as a textile sealing portion or textile membrane and may comprise atextile material having an air impermeable property (e.g., a materiallayered, coated or otherwise applied thereon).

The support structure 3120 may have an aperture formed therein providingan inner edge of the support structure 3120 along which the sealingportion 3130 (e.g., an outer perimeter of the sealing portion 3130) maybe attached to the support structure 3120 such that the sealing portion3130 extends radially inwardly of the seal-forming structure 3100 beyondor to a further extent than the support structure, as shown for examplein FIGS. 12-21 . For example, the sealing portion 3130 may be moldedaround the inner edge of the support structure 3120 or connected to thesupport structure 3120 in other suitable ways, as will be describedlater.

Referring to FIGS. 12-15 , the seal-forming portion 3100 has a wallstructure that may include lateral support regions 3122 having anincreased thickness as compared to other portions of the wall structureof the support structure 3120. At each lateral most side of theseal-forming structure 3100, a lateral support region 3122 may beprovided. The seal-forming structure 3100 may include two lateralsupport regions 3122, each spaced distal from a plane bisecting theseal-forming structure 3100 that would be parallel to the patient'ssagittal plane, in use. The lateral support regions 3122 may be thethickest portions of the seal-forming structure 3100 to provideresistance to lateral displacement (e.g., caused by the patient sleepingon the side of their head such that the pillow pushes laterally againstthe seal-forming structure) and to provide robust engagement against thepatient's ala. The lateral support regions 3122 may have a thickness ofapproximately 0.9 mm to approximately 1.5 mm, or approximately 1.3 mm toapproximately 1.4 mm, or approximately 1.3 mm, or approximately 1 mm toapproximately 1.5 mm Due to the lateral support regions 3122 being thethickest regions of the seal-forming structure 3100 in the depictedexamples, the lateral support regions 3122 may also provide the greatestresistance to deformation.

The textile membrane 3130 may be formed such that the textile membrane3130 forms part of the portion of the seal-forming structure 3100 thatcurves from the anterior side of the seal-forming structure 3100 to theposterior face-contacting side, as described earlier. That is, thetextile membrane 3130 is in contact with the support structure 3120 inthe transition portion 36 such that the textile membrane portion 3130may be configured to engage the subalare region of the patient's face(i.e., the region where the ala terminate at the lip superior proximatethe nasolabial sulcus), which is a region of particularly complexgeometry. The subalare region of a patient's face presents particularlycomplex geometry because at least three facial surfaces—the ala, the lipsuperior, and the cheek—converge at this region. As a result, theseal-forming structure 3100 may be more flexible and compliant (e.g.,not under tension proximate the outer periphery of the textile membrane3130) so as to more readily conform to the patient's facial contours.

As described earlier, FIGS. 19-21 show grip pads 3150 on the surface ofthe textile membrane 3130.

5.3.2.3 Positioning and Stabilising Structure

The seal-forming structure 3100 of the patient interface 3000 of thepresent technology may be held in sealing position in use by thepositioning and stabilising structure 3300.

In one form the positioning and stabilising structure 3300 provides aretention force at least sufficient to overcome the effect of thepositive pressure in the plenum chamber 3200 to lift off the face.

In one form the positioning and stabilising structure 3300 provides aretention force to overcome the effect of the gravitational force on thepatient interface 3000.

In one form the positioning and stabilising structure 3300 provides aretention force as a safety margin to overcome the potential effect ofdisrupting forces on the patient interface 3000, such as from tube drag,or accidental interference with the patient interface.

In one form of the present technology, a positioning and stabilisingstructure 3300 is provided that is configured in a manner consistentwith being worn by a patient while sleeping. In one example thepositioning and stabilising structure 3300 has a low profile, orcross-sectional thickness, to reduce the perceived or actual bulk of theapparatus. In one example, the positioning and stabilising structure3300 comprises at least one strap having a rectangular cross-section. Inone example the positioning and stabilising structure 3300 comprises atleast one flat strap.

In one form of the present technology, a positioning and stabilisingstructure 3300 is provided that is configured so as not to be too largeand bulky to prevent the patient from lying in a supine sleepingposition with a back region of the patient's head on a pillow.

In one form of the present technology, a positioning and stabilisingstructure 3300 is provided that is configured so as not to be too largeand bulky to prevent the patient from lying in a side sleeping positionwith a side region of the patient's head on a pillow.

In one form of the present technology, a positioning and stabilisingstructure 3300 is provided with a decoupling portion located between ananterior portion of the positioning and stabilising structure 3300, anda posterior portion of the positioning and stabilising structure 3300.The decoupling portion does not resist compression and may be, e.g. aflexible or floppy strap. The decoupling portion is constructed andarranged so that when the patient lies with their head on a pillow, thepresence of the decoupling portion prevents a force on the posteriorportion from being transmitted along the positioning and stabilisingstructure 3300 and disrupting the seal.

In one form of the present technology, a positioning and stabilisingstructure 3300 comprises a strap constructed from a laminate of a fabricpatient-contacting layer, a foam inner layer and a fabric outer layer.In one form, the foam is porous to allow moisture, (e.g., sweat), topass through the strap. In one form, the fabric outer layer comprisesloop material to engage with a hook material portion.

In certain forms of the present technology, a positioning andstabilising structure 3300 comprises a strap that is extensible, e.g.resiliently extensible. For example the strap may be configured in useto be in tension, and to direct a force to draw a seal-forming structure3100 into sealing contact with a portion of a patient's face. In anexample the strap may be configured as a tie.

In one form of the present technology, the positioning and stabilisingstructure comprises a first tie, the first tie being constructed andarranged so that in use at least a portion of an inferior edge thereofpasses superior to an otobasion superior of the patient's head andoverlays a portion of a parietal bone without overlaying the occipitalbone.

In one form of the present technology suitable for a nasal-only mask orfor a full-face mask, the positioning and stabilising structure includesa second tie, the second tie being constructed and arranged so that inuse at least a portion of a superior edge thereof passes inferior to anotobasion inferior of the patient's head and overlays or lies inferiorto the occipital bone of the patient's head.

In one form of the present technology suitable for a nasal-only mask orfor a full-face mask, the positioning and stabilising structure includesa third tie that is constructed and arranged to interconnect the firsttie and the second tie to reduce a tendency of the first tie and thesecond tie to move apart from one another.

In certain forms of the present technology, a positioning andstabilising structure 3300 comprises a strap that is bendable and e.g.non-rigid. An advantage of this aspect is that the strap is morecomfortable for a patient to lie upon while the patient is sleeping.

In certain forms of the present technology, a positioning andstabilising structure 3300 comprises a strap constructed to bebreathable to allow moisture vapour to be transmitted through the strap.

In certain forms of the present technology, a system is providedcomprising more than one positioning and stabilizing structure 3300,each being configured to provide a retaining force to correspond to adifferent size and/or shape range. For example the system may compriseone form of positioning and stabilizing structure 3300 suitable for alarge sized head, but not a small sized head, and another. suitable fora small sized head, but not a large sized head.

5.3.2.3.1 Positioning and Stabilising Structure of the PresentTechnology

FIG. 6 depicts an example of the present technology, including apositioning and stabilising structure 3300. In this example, thepositioning and stabilising structure 3300 includes lateral portions3302 and superior portions 3304 in the form of conduits that direct aflow pressurised gas from a hub 3306 to ends 3314. The positioning andstabilising structure 3300 may be arranged such that the hub 3306 andthe decoupling structure 3500 are positioned superior to the patient'shead in use. As described below, the decoupling structure 3500 may berotatable within the hub 3306 and when the patient is wearing thepatient interface 3000, e.g., during therapy, the location of the hub3306 and the decoupling structure 3500 superior to the patient's headallows the patient to move more freely without becoming entangled withthe air circuit 4170.

The positioning and stabilising structure 3300 may be constructed ofsilicone. For example, the lateral portions 3302, the superior portions3304, the hub 3306, and the lateral ends 3314 may able constructed ormolded from a single piece of silicone.

The superior portions 3304 of the positioning and stabilising structure3300 have ridges and valleys (or concertina sections) that allow thesuperior portions 3304 to conform to the shape of the correspondingportion of the patient's head in use. The ridges and valleys of thesuperior portions 3304 allow the superior portions 3304 to be extendedand contracted along the longitudinal axis to accommodate larger orsmaller heads. The ridges and valleys of the superior portions 3304allow the superior portions 3304 to be flexed to different radii ofcurvature to accommodate patient heads of different shapes and sizes.

The lateral portions 3302 of the positioning and stabilising structure3300 may not be formed with the ridges and valleys of the superiorportions 3304. Therefore, the lateral portions 3302 may be lessextensible and flexible than the superior portions 3304, which may beadvantageous because there is less variability in the shape and size ofthe lateral sides of a patient's head.

The ends 3314 may connect to respective plenum chamber lateral ends3202. As described above, the plenum chamber lateral ends 3202 receivethe flow of pressurised gas from the positioning and stabilisingstructure 3300, which passes through the plenum chamber 3200, throughthe seal-forming structure 3100, and on to the patient's airways. Asdescribed above, the ends 3314 may connect to the plenum chamberconnectors 3204 of a respective plenum chamber lateral end 3202.

The positioning and stabilising structure 3300 may be structured andarranged to direct a force/tension provided by the lateral portions 3302into a partially superior and partially posterior force vector appliedto the plenum chamber 3200. The partially superior and partiallyposterior force vector urges, in particular, the textile membrane of theseal forming structure 3100 into sealing contact with an underside ofthe patient's nose contacting, e.g., at or below the pronasale and atleast above the upper vermillion.

The lateral portions 3302 may also each include a tab 3308 that receivesa posterior strap end portion 3311 of a posterior strap 3310. Theposterior strap 3310 may be length-adjustable, e.g., with a hook andloop material arrangement whereby one of the posterior strap end portion3311 and the remainder of the posterior strap 3310 includes hookmaterial on its exterior while the other includes loop material on itsexterior. The length adjustability of the posterior strap 3310 allowstension on the lateral portions 3302 to be increased to pull theseal-forming structure 3100 into sealing engagement with the patient'sface at a desired amount of pressure (i.e., sufficiently tight to avoidleaks while not so tight as to cause discomfort).

The lateral portions 3302 may also be provided with sleeves 3312 thatcushion the patient's face against the lateral portions 3302. Thesleeves 3312 may be constructed of a breathable textile material thathas a soft feel. The sleeves 3312 may be removable from the lateralportions 3302 after the ends 3314 are removed from the plenum chamberlateral ends 3202.

In some forms (see e.g., FIG. 7 ), a positioning and stabilizingstructure 6300 may include a textile tube 6350 with a left arm 6305 anda right arm 6307. The textile tube 6350 may be formed with a first sidethat is configured to contact the patient. This may be referred to asthe inner layer 6352. The textile conduit may also include a second sidethat is attached to the inner layer 6352, but faces away from thepatient that may be referred to as the outer layer 6354. The inner layer6352 and the outer layer 6354 may each be secured to each other alongthe edges of the inner layer 6352 and the outer layer 6354 such that achannel or passageway is formed between the seams of the inner layer6352 and the outer layer 6354. That is, the space between the seamsremains unattached and forms an air passage 6372. The inner layer 6352and the outer layer 6354 may be joined using various techniques thatimpart particular properties to the seam or joint. For example, in someforms, the seams are formed using ultrasonic welding, radio frequencywelding, as well as cut and weld techniques. Heat may be applied inparticular areas that activates a thermoset or thermoplastic materialused in tube 6350. This heat may not only be used to join the layerstogether, but may also be used to thermoform the layers, such as outerlayer 6354. Further, in some forms stitching or an adhesive such as aglue may be utilized to join the layers together. In some forms,stitching is not used. In still further forms, material beyond what islocated within the layers is not utilized to join the inner and outerlayers 6352, 6354 of tube. For example, in some forms the inner andouter layers 6352, 6354 may be formed such that no additional materialsuch as glue or stitching, is necessary to join the inner and outerlayers 6352, 6354 together.

Each of the inner layer 6352 and the outer layer 6354 may include aninterior surface and an exterior surface. The interior surface of theinner layer 6352 is the surface that faces the exterior layer 6354. Theinterior surface of the exterior layer 6354 is the surface that facesthe inner layer 6352. Likewise, the exterior surface of the outer layer6354 faces away from the inner layer 6352 and the exterior surface ofthe inner layer 6352 faces away from the outer layer 6354. Further, informs that include a single sheet, the interior surface is the surfaceof the sheet that faces inwards and towards itself.

In some forms, the sheet or sheets of the tube may include an airimpermeable layer or membrane. In some forms, the interior surface ofboth of the layers includes a membrane that is configured to restrict orrestrain air from passing through the layer from the interior surface tothe exterior surface. The impermeable layer may be a thin layer that isless than the thickness of the textile sheets of the inner layer orouter layer. In other forms, the impermeable layer may be greater thanthe thickness of the sheets of textiles of either of the layers. Theimpermeable layer or membrane or film may be completely impermeable toair transfer or may be formed to allow a predetermined rate or airtransfer and particular pressures.

The membrane may be formed of thermoplastic or thermoset materials suchthat when exposed to a particular temperature membrane material may beable to be molded or shaped into a particular form and then cures orsolidifies or sets upon cooling. In some forms the membrane may beformed of silicone or polyurethane. In some forms, outer layer 6354 maybe pre-formed such that in an unpressurized or supported state, outerlayer 6354 is pre-positioned and pre-formed to extend away from innerlayer 6352 between the opposing joints 6312. That is, outer layer 6354may support its own weight such that when not supported by pressurizedair or other support mechanism, outer layer 6354 remains spaced frominner layer 6352 between joints 6312.

In contrast, inner layer 6352 may be a floppy component. Inner layer6352 may be attached and secured to the edges of outer layer 6354 suchthat inner layer 6352 is a substantially planar layer.

As shown in FIG. 8 , and in particular FIG. 9 , inner layer 6352comprises a textile sheet 6360 along with membrane 6362. Textile sheet6360 may be formed of felt, foam, woven, knit, or non-woven material orother network of fibers.

Outer layer 6354 includes tube sheet 6364 and outer covering 6366. Insome forms, both sides of tube sheet 6364 may be covered with amembrane. As shown in FIG. 10 , tube sheet 6364 includes membrane 6368exposed to the chamber of tube 6350 and membrane 6370 along an oppositesurface of tube sheet 6364. membrane 6368 may assist in providing a sealbetween inner layer 6352 and outer layer 6354 as well as forming an airtight tube. Membrane 6370 may assist in joining tube sheet 6364 to outercovering 6366.

5.3.2.4 Vent

In one form, the patient interface 3000 includes a vent 3400 constructedand arranged to allow for the washout of exhaled gases, e.g. carbondioxide.

In certain forms the vent 3400 is configured to allow a continuous ventflow from an interior of the plenum chamber 3200 to ambient whilst thepressure within the plenum chamber is positive with respect to ambient.The vent 3400 is configured such that the vent flow rate has a magnitudesufficient to reduce rebreathing of exhaled CO₂ by the patient whilemaintaining the therapeutic pressure in the plenum chamber in use.

One form of vent 3400 in accordance with the present technologycomprises a plurality of holes, for example, about 20 to about 80 holes,or about 40 to about 60 holes, or about 45 to about 55 holes.

The vent 3400 may be located in the plenum chamber 3200. The vent 3400may comprise a plurality of holes, as described above. The holes of thevent 3400 may be divided into two groups spaced apart laterally. Theaxis of the flow path through each of the holes of the vent 3400 may beparallel such that cross-flow is avoided to prevent generation ofadditional noise. The vent holes may be circular.

The holes of the vent 3400 may decrease in radius from the interior ofthe plenum chamber 3200 to the exterior. Each vent hole is provided witha draft angle. Each hole has a smaller diameter at its anterior end thanat its posterior end. The draft angle means that the holes do not have asmall cross section across the entire chassis thickness, which helps toprovide effective carbon dioxide wash out at high levels ofhumidification. Additionally, a larger draft angle may result in aplenum chamber 3200 that is easier to manufacture, especially when theplenum chamber 3200 is formed from an injection moulded plasticsmaterial. The draft angle enables relatively thick vent pins to be usedin the mould and easier ejection.

The holes of the vent 3400 may be provided in two sets towards themiddle of the plenum chamber 3200 and the sets may be symmetrical acrossthe centreline of the plenum chamber 3200. Providing a pattern ofmultiple vent holes may reduce noise and diffuse the flow concentration.

The holes of the vent 3400 may be placed at an optimum distance awayfrom the centreline of the plenum chamber 3200. Placing the holes of thevent 3400 towards the centreline may advantageously reduce the chancethat the vent holes are blocked when the patient is sleeping on theirside. However, placing the vent holes too close to the middle of theplenum chamber 3200 may result in excessive weakening of the plenumchamber 3200 at the center, especially since the cross-section of theplenum chamber 3200 in the depicted examples is smallest at the centerdue to the overall shape of the plenum chamber 3200. The location of theholes of the vent 3400 may avoid hole blockage during side sleep whileleaving the middle section of the chassis sufficiently strong.

The size of each vent hole and the number of vent holes may be optimisedto achieve a balance between noise reduction while achieving thenecessary carbon dioxide washout, even at extreme humidification. In thedepicted examples, the vent holes of the vent 3400 may not provide thetotal amount of venting for the system. The decoupling structure 3500may include a decoupling structure vent 3402. The decoupling structurevent 3402 may include one hole or a plurality of holes through thedecoupling structure 3500. The decoupling structure vent 3402 mayfunction to bleed off excess pressure generated by the RPT device 4000before reaching the patient, while the vent 3400 may function to washoutcarbon dioxide exhaled by the patient during therapy.

In some examples, a vent insert (not shown) attaches, removably orpermanently, to the plenum chamber 3200 at a vent insert opening. Thevent insert may be constructed from a material that is more flexiblethan the material of the plenum chamber 3200. In one example, heat andmoisture exchanging (HME) material (e.g., a foam) is housed in theremovable vent, in order to humidify air the patient inhales, withoutthe need for a separate humidifier. The vent insert may be removable inorder to allow the patient to replace the HME material after a certaintime period as past, with a fresh, clean sheet of HME material. Inaddition, the entire vent structure could be replaceable (e.g., asopposed to the HME material alone).

5.3.2.5 Decoupling Structure(s)

In one form the patient interface 3000 includes at least one decouplingstructure, for example, a swivel or a ball and socket.

The hub 3306, described above, is connected to a decoupling structure3500, which is a rotatable elbow in these examples. The decouplingstructure 3500 may be rotatable 360° within the hub 3306 in use. Thedecoupling structure 3500 may be removable from the hub 3306 by manuallydepressing buttons 3504 to release catches (not shown) from within thehub 3306.

The decoupling structure 3500 may also include a swivel 3502 that allowsfor rotatable connection to an air circuit 4170.

The rotatability of the decoupling structure 3500, the decouplingstructure 3500 being in the form of an elbow, and the rotatability ofthe swivel 3502 on the decoupling structure 3500 may all increased thedegrees of freedom, which in turn reduce tube drag and torque on thepatient interface 3000 caused by the connection to the air circuit 4170.

5.3.2.6 Connection Port

Connection port 3600 allows for connection to the air circuit 4170.

5.3.2.7 Forehead Support

In one form, the patient interface 3000 includes a forehead support3700.

5.3.2.8 Anti-Asphyxia Valve

In one form, the patient interface 3000 includes an anti-asphyxia valve.

5.3.2.9 Ports

In one form of the present technology, a patient interface 3000 includesone or more ports that allow access to the volume within the plenumchamber 3200. In one form this allows a clinician to supplysupplementary oxygen. In one form, this allows for the directmeasurement of a property of gases within the plenum chamber 3200, suchas the pressure.

5.3.3 Full Face Cushion

Referring to FIGS. 26-33 , patient interface 6000 includes cushionassembly 6105 having a seal-forming structure 6100 that is configured toseal separately around the patient's nares and mouth (e.g., an oro-nasalcushion assembly or ultra-compact full face mask). The cushion assembly6105 is at least partially formed by a plenum chamber 6200 and aseal-forming structure 6100 that is attached to the plenum chamber inaccordance with an example of the present technology.

Referring to FIGS. 22-25 and 34-39 , a cushion assembly 9105 is shown.Cushion assembly 9105 is similar to cushion assembly 6105 and has aseal-forming structure 9100 that is configured to seal separately aroundthe patient's nares and mouth (e.g., an oro-nasal cushion assembly orultra-compact full face mask). The cushion assembly 9105 is at leastpartially formed by a plenum chamber 9200 and a seal-forming structure9100 that is attached to the plenum chamber in accordance with anexample of the present technology.

The cushion assembly 9105 includes nasal portion 9101, nasal portionholes 9103, oral portion 9102, oral portion hole 9104, cavity 9001,support structure 9120, sealing portion 9130, and vent 9400 which aresimilar to the features described in FIG. 26-33 . The description ofFIGS. 26-33 may generally apply to FIGS. 22-25 and 34-39, and manysimilarities and differences not discussed separately. A pair of plenumchamber holes are configured to receive a flow of air.

The cushion assembly 9105 (e.g., specifically the nasal portion 9101)may include at least one curved surface as a result of the connection tothe support structure 9120. This curved surface may extend from ananterior to a posterior side of the cushion assembly 9105 (see e.g.,FIG. 24 ). A similar curvature may be present on the cushion assembly6105 (see e.g., FIGS. 30 and 31 ). However, unlike the cushion assembly6105, the cushion assembly 9105 (e.g., specifically the nasal portion9101) may include at least one curved surface, which may be the resultof a crimp in the nasal portion 9101, which is described in more detailbelow. The curved surface of the cushion assembly 9105 resulting fromthe crimp may extend along a lateral direction of the patient's face(e.g., in the left-right direction) while the cushion assembly 9105 isin use. For example, the curved surface of the cushion assembly 9105that results from the crimp may curve about an axis perpendicular to anaxis through section line 36-36 (see e.g., FIG. 34 ), and/or about athird axis 13000 (described in detail below). The curved surfaceresulting from the crimp may also have a positive curvature relative tothe patient's face.

As described earlier, FIGS. 37-39 show grip pads 9150 on the surface ofthe textile membrane. The grip pads 9150 may be on the first sealingportion 9131 and/or the second sealing portion 9132. Althoughillustrated with the cushion assembly 9105, the grip pads 9150 may alsobe incorporated into the cushion assembly 6105.

Referring to FIG. 33-1 , patient interface 21000 includes a cushionassembly 21105 with a seal-forming structure 21100 that is configured toseal around the patient's nares and mouth (e.g., an oro-nasal cushionassembly or ultra-compact full face mask). The cushion assembly 21105 issimilar to the cushion assemblies 6105 and 9105. The cushion assembly21105 is at least partially formed by a plenum chamber 21200 and theseal-forming structure 21100 that is attached to the plenum chamber inaccordance with an example of the present technology. The seal-formingstructure 21100 may also include a curved surface like the nasal portion9101.

Referring to FIG. 33-2 , patient interface 23000 includes a cushionassembly 23105 with a seal-forming structure 23100 that is configured toseal around the patient's nares and mouth (e.g., an oro-nasal cushionassembly or ultra-compact full face mask). The cushion assembly 23105 issimilar to the cushion assemblies 6105 and 9105. The cushion assembly23105 is at least partially formed by a plenum chamber 23200 and theseal-forming structure 23100 that is attached to the plenum chamber inaccordance with an example of the present technology. The seal-formingstructure 23100 may also include a curved surface like the nasal portion9101.

Referring to FIGS. 33-3 to 33-11 , patient interface 25000 includes acushion assembly 25105 with a seal-forming structure 25100 that isconfigured to seal around the patient's nares and mouth (e.g., anoro-nasal cushion assembly or ultra-compact full face mask). The cushionassembly 25105 is similar to the cushion assemblies 6105 and 9105. Thecushion assembly 25105 is at least partially formed by a plenum chamber25200 and the seal-forming structure 25100 that is attached to theplenum chamber in accordance with an example of the present technology.The seal-forming structure 25100 may also include a curved surface likethe nasal portion 9101.

The full face cushions of FIGS. 22-39 may have some similarities to thenasal cushion 3000 described above. For example, the seal-formingstructures described in more detail below, may have tension selectivelyapplied in order to assist in forming a resulting shape (e.g., atwo-dimensional shape or a three-dimensional shape). Varioussimilarities and differences between the full face cushions and thenasal cushion 3000 are described below.

5.3.3.1 Plenum Chamber

The plenum chamber 6200 has a perimeter that is shaped to becomplementary to the surface contour of the face of an average person inthe region where a seal will form in use. In use, a marginal edge of theplenum chamber 6200 is positioned in close proximity to an adjacentsurface of the face. Actual contact with the face is provided by theseal-forming structure 6100. The seal-forming structure 6100 may extendin use about the entire perimeter of the plenum chamber 6200.

In certain forms of the present technology, the plenum chamber 6200 isconstructed from a relatively rigid material (e.g., polycarbonate) ascompared to the seal-forming structure 6100. In another example, theplenum chamber 6200 is constructed from a flexible material (e.g.,silicone, textile, etc.), and may have a similar rigidity as compared tothe seal-forming structure 6100. In another example, the plenum chamber6200 may be constructed from a transparent material, e.g. a transparentpolycarbonate. The use of a transparent material can reduce theobtrusiveness of the patient interface 6000, and help improve compliancewith therapy. The use of a transparent material can aid a clinician inobserving how the patient interface 6000 is located and functioningand/or in observing any build-up of debris (e.g., dirt, mold, etc.).

In certain forms of the present technology, the plenum chamber 6200 isconstructed from a translucent material. The use of a translucentmaterial can reduce the obtrusiveness of the patient interface 6000, andhelp improve compliance with therapy.

The plenum chamber 6200 according to examples of the present technologymay include a plenum chamber hole on each lateral side. The plenumchamber hole may provide pneumatic communication between the conduitconnectors 6800, which are described in greater detail below, and thecavity 6001. A connection rim portion around each plenum chamber holemay facilitate a mechanical connection, e.g., snap-fit or friction fit,with the respective conduit connector. The plenum chamber 6200 may beconstructed of a sufficiently rigid material to provide audible and/ortactile feedback to the patient when the conduit connectors 6800 areconnected to or removed from the plenum chamber 6200.

The seal-forming structure 6100 may be sealingly connected to the plenumchamber 6200. The connection may be permanent or the seal-formingstructure 6100 may be removable from the plenum chamber 6200. Theseal-forming structure 6100 may be molded (e.g., overmoulded, injectionmolded, etc.) to the plenum chamber 6200. The seal-forming structure6100 and the plenum chamber 6200 may be joined by a mechanicalconnection in which no chemical bond is formed between the plenumchamber 6200 and the seal-forming structure 6100.

5.3.3.2 Seal-Forming Structure

Referring to FIGS. 26-33 , the seal-forming structure 6100 may include anasal portion 6101 that has at least one hole (e.g., a pair of nasalportion holes 6103) to seal with, and convey pressurized air to, thepatient's nares. The depicted examples provide two separate holes 6103that each corresponds to one of the patient's nares to provide the flowof air to both of the patient's nares. There may also be a bridgeportion 6106 positioned between the naris openings 6103. In analternative example, a single hole may be used to provide the flow ofair to both of the patient's nares. A further alternative may includethree or more holes. Unlike the bridge portion 3104, the bridge portion6106 may not be selectively tensioned. For example, the bridge portion6106 and the surrounding material of the nasal portion 6101 may be heldunder tension together, instead of tension being applied only to thebridge portion 6106.

Referring briefly to FIGS. 22-25 and 34-39 , the bridge portion 9106 maybe selectively tensioned in a similar manner as the bridge portion 3104.For example, the bridge portion 9106 may be tauter than the surroundingfirst sealing portion 9131.

With continued reference to FIGS. 26-33 , the seal-forming structure6100 may include an oral portion 6102 having an oral portion hole 6104to seal with the patient's mouth. In some examples, the oral portion6102 is held at least partially in tension (e.g., at any number ofdiscrete locations) when not in use (i.e., when not contacting thepatient's face). For example, the oral portion may be in tension at ajoin with the support structure 6120, but relaxed on an exposed sealingedge (e.g., an inner edge proximate to an opening of the cavity 6001).In some examples, the oral portion 6102 is entirely in a relaxed statewhen not in use. In any of the examples, contact with the patient's facemay stretch the oral portion 6102, so that it is under tension while inuse.

The seal-forming structure 6100 may at least partly form a cavity 6001that is pressurized by the flow of air. The plenum chamber 6200 may bejoined to the seal-forming structure 6100 to further form the cavity6001.

The seal-forming structure 6100 may include a support structure 6120that provides support to a sealing portion 6130 (e.g., a textilemembrane). The sealing portion is configured to sealingly engage thepatient's face. The sealing portion 6130 is large enough (e.g., curvesin the anterior direction a sufficient amount) so that only the sealingportion 6130 (e.g., only the textile membrane) may contact and sealinglyengage a patient's face. Alternatively, the support structure 6120 mayalso be constructed from a textile material.

In one example, the seal-forming structure 6100 may include a supportstructure 6120 having at least two regions (e.g., two, three, or fourregions) of different thickness (e.g., seal-forming structure 6100comprises support structure 6120 which has a wall structure havinglateral support regions (see e.g., 3122 in FIGS. 58 and 59 ) of anincreased thickness with respect to other portions of the wallstructure). For example, as shown in FIGS. 58 and 59 , some portions3123 of the support structure 3120 may be thicker than other portions3124, 3126 of the support structure 3120. For example, thicker portions3123 may be adjacent to or connecting to the plenum chamber and portions3124, 3126 may be adjacent to or connecting to the textile membrane 3130so as to provide structural stability at the connection with the plenumchamber 3200 and flexibility at the interface with the patient.Alternatively, the thicker portions of the lateral support regions 3122may be located, for example, at the corner of nose region of theseal-forming structure (and e.g., may connect directly to the textilemembrane), to ensure adequate sealing in the subalare region of thepatient's face.

As described above, the seal-forming structure 6100 may be sealinglyconnected to the plenum chamber 6200. The support structure 6120 may beless rigid than the plenum chamber 6200 and may be constructed fromsilicone, foam (e.g., polyurethane foam), polyurethane solid material,thermoplastic elastomers (e.g., thermoplastic polyurethane), suitableplastics, or other suitable materials, as will be described later.Further, the sealing portion 6130 may be less rigid than the supportstructure 6120 and may be constructed from a textile material 6130 suchas nylon, polyester, nylon and polyester mix, microfiber orpolyurethane, for example, as will be described in more detail later.

In the example of FIG. 32 , the support structure 6120 may extend intothe cavity 6001 forming an underlying cushion 6121 to provide support tothe sealing portion 14130. The underlying cushion 6121 and the sealingportion 6130 may form a dual wall structure around the perimeter ofsealing portion. In alternative examples, a second or third underlyingcushion layer may be provided to form a triple or quadruple wallstructure. In the example of FIG. 32 , the underlying cushion isconstructed of a foam material (e.g., polyurethane foam). In analternative example, the underlying cushion 6122 may be constructed ofsilicone, as shown in FIG. 33 . However, it will be recognized that theunderlying cushion may be constructed from other suitable materials(e.g., textile).

The sealing portion 6130 may be constructed from two different pieces ofa textile membrane. For example, one piece 6131 may be used to sealaround the patient's nose, while a separate piece 6132 may be used toseal around the patient's mouth. The sealing portions 6131, 6132 may beused to independently seal around the respective orifice. In otherwords, the first or upper sealing portion 6131 may not contact the areaaround the patient's mouth, and the second or lower sealing portion 6132may not contact the area around the patient's nose.

As shown in FIGS. 26-33 , the first sealing portion 6131 is disposed ina superior portion (i.e., when in use) of the patient interface 6000 ascompared to the second sealing portion 6132. The first sealing portion6131 forms a round (e.g., generally tri-oval) perimeter that sealsaround the patient's nares while in use.

In some forms, the first sealing portion 6131 may contact a regionbetween the nasal ala and the lip superior, while leaving the pronasaleexposed (see e.g., FIGS. 23-25 illustrating the similar first sealingportion 9131). The textile membrane of the first sealing portion 6131may be the only material of the seal-forming structure 6100 to contactthe patient in this region. In other words, the second sealing portion6132 and the support structure 6120 do not contact the patient in thisregion. This may assist in improving patient compliance because thepatient may only contact a textile layer in this region of their face,which they may more closely associate with bedclothes, instead of amedical device.

The second sealing portion 6132 is disposed in an inferior portion(i.e., when in use and as compared to the first sealing portion 6131) ofthe patient interface 6000. In the illustrated example, the secondsealing portion 6132 forms a generally U-shape, and seals around aportion of the patient's mouth. The textile membrane that forms thesecond sealing portion 6132 does not extend completely around thepatient's mouth. In other words, a material other than the textilemembrane may contact the patient in order to form a seal around thepatient's mouth. In this example, the support structure 6120 (e.g., asilicone material) is molded between free ends of the second sealingportion 6132 in order to complete an oral portion hole 6104. The textilemembrane of the second sealing portion 6132 may contact the patient'slip inferior, a region outside the patient's cheillion, and a portion ofthe patient's lip superior, and may not contact the central portion ofthe patient's lip superior (e.g., proximate to the patient's philtrum).The support structure 6120 extends across the patient's philtrum,between the ends of the second sealing portion 6132. A combination ofthe textile membrane of the sealing portion 6130 and the siliconematerial of the support structure 6120 may be responsible for creating aseal around the patient's mouth.

The support structure 6120 extends from a lower surface of the firstsealing portion 6131 to an opening of the cavity 6001. In other words,the first sealing portion 6131 is separated from the second sealingportion 6132 by the support structure 6120. The material (e.g.,silicone) of the support structure 6120 also assists in coupling thefirst sealing portion 6131 and the second sealing portion 6132 to eachother during the manufacturing process.

As shown in FIG. 33-1 , the second sealing portion 21130 b extendscompletely around the patient's mouth. In other words, textile membranecontacts the philtrum as opposed to the support structure 21120. Thesupport structure 21120 (e.g., silicone material) is disposed in theinferior/superior direction between the first and second sealingportions 21130 a, 21130 b (e.g., first and second sub-sections). Thesupport structure 21120 may slightly contact the patient's lip superior,although sealing is accomplished primarily or exclusively via thetextile membrane in the first and second sealing portions 21130 a, 21130b. In other words, a location where support structure 21120 contacts thepatient's skin may be unpressurized and/or exposed to ambient duringtherapy. Having the second support structure 21130 b extend all the wayaround the patient's mouth may provide the patient with more comfort ascompared with the U-shaped second sealing structure 21130 b (e.g.,because the patient may find the textile membrane more comfortable thanthe silicone), which may increase the patient's compliance with thetherapy.

In another example of the patient interface 23000, as shown in FIG. 33-2, the second sealing portion 23130 b is U-shaped. However, the philtrumand central portion of the lip superior are contacted by textilemembrane. In this example, the first sealing portion 23130 a extendsdown to an edge of the oral portion hole 23104. In other words, thefirst sealing portion 23130 a is responsible for forming the seal aroundthe patient's nose, and is also partially responsible for forming theseal around the patient's mouth. The U-shaped second sealing portion23130 b extends substantially around the remainder of the patient'smouth (although a small portion of the support structure 23120 isdisposed laterally between the first and second sealing portions 23130a, 23130 b in the left/right direction). This example may providesimilar comfort benefits as described above with respect to FIG. 33-1(e.g., because substantially all of the patient's nose and mouth contactby the patient interface 23000 is contacted by the textile membrane).However, the example of FIG. 33-2 may be easier to manufacture becausethe support material 23120 between the first and second seal portions23130 a, 23130 b is removed in the superior/inferior direction. Thesmall portions of the support structure 23120 between the sealingportions 23130 a, 23130 b may assist in forming the pressurized volumearound the patient's mouth.

In other example of the patient interface 25000, as shown in FIG. 33-3 ,the sealing portion 25130 is formed from a single piece of textilematerial. In other words, the first and second sealing portions 25130 a,25130 b are not constructed from separate pieces of material. The singlepiece of material that forms the sealing portion 25130 is responsiblefor forming a seal around both the patient's nose and the patient'smouth. The sealing portion 25130 may have a similar outer perimeter asdescribed above (e.g., in examples of the patient interface 25000 havingfirst and second sealing portions 25130). In some examples, the sealingportion 25130 may only seal around its outer perimeter, since notsealing against the patient's lip superior may not allow air to leak outof the seal-forming structure 25100. However, the sealing portion 25130may still seal against the patient's lip superior so that pressurizedair is more directly delivered to the patient's airways. By using asingle piece of textile membrane to form the sealing portion 25130, thesupport structure 25120 may not contact the patient's upper lip.Additionally, manufacturing the patient interface may be easier becausethe thin strip of support structure 25120 no longer needs to be formedbetween two pieces of textile membrane to connect them together. Thus,the molding process may be simplified so that small amounts of amaterial like silicone do not need to flow between, but not cover atextile layer 10133.

As shown in FIGS. 22 to 25 and 31-1 to 39 , the respective seal formingstructures may all have a three-dimensional shape. Specifically, therespective first sealing portions may have a curved surface (e.g., inleft-right direction), as opposed to the flat surface (e.g., in theleft-right direction) shown in FIGS. 26-33 . The three-dimensional shapemay be formed, at least in part, by selectively applying tension to thebridge portion of the respective first sealing portion. Tension may notbe applied to the material of the first sealing portion surrounding thebridge portion on the respective seal forming structures so that thefirst sealing portion may include a curved shape.

In any of these embodiments (e.g., FIGS. 22-39 ), the strength of theseal against the patient's face is substantially the same. For example,having textile material alone, or a combination of textile and siliconematerial does not substantially effect the quality of the seal (i.e.,increase or decrease areas of leak). Different patients (e.g., differentfacial geometries) may be better suited for one of the particularexamples over the others (e.g., because of comfort, fit, etc.).Additionally, while examples with more textile coverage may provideadditional comfort to the patient, the added comfort may be minimal(e.g., since the support structure 6120 provides minimal contact inexamples with both the first and second sealing portions 6131, 6132).

5.3.3.3 Positioning and Stabilising Structure

The seal-forming structure 9100 of the patient interface 9000 of thepresent technology may be held in sealing position in use by thepositioning and stabilising structure 9300. While the positioning andstabilizing structure 9300 is specifically shown with the patientinterface 9000, it may be used with any of the full face cushions (e.g.,any example in FIGS. 22-39 ). The positioning and stabilizing structure9300 may also be similar to the positioning and stabilizing structure3300.

In one form the positioning and stabilising structure 9300 provides aretention force at least sufficient to overcome the effect of thepositive pressure in the cavity 9001 to lift off the face.

In one form the positioning and stabilising structure 9300 provides aretention force to overcome the effect of the gravitational force on thepatient interface 9000.

In one form the positioning and stabilising structure 9300 provides aretention force as a safety margin to overcome the potential effect ofdisrupting forces on the patient interface 9000, such as from tube drag,or accidental interference with the patient interface.

In one form of the present technology, a positioning and stabilisingstructure 9300 is provided that is configured in a manner consistentwith being worn by a patient while sleeping. In one example thepositioning and stabilising structure 9300 has a low profile, orcross-sectional thickness, to reduce the perceived or actual bulk of theapparatus. In one example, the positioning and stabilising structure9300 comprises at least one strap having a rectangular cross-section. Inone example the positioning and stabilising structure 9300 comprises atleast one flat strap.

In one form of the present technology, a positioning and stabilisingstructure 9300 is provided that is configured so as not to be too largeand bulky to prevent the patient from lying in a supine sleepingposition with a back region of the patient's head on a pillow.

In one form of the present technology, a positioning and stabilisingstructure 9300 is provided that is configured so as not to be too largeand bulky to prevent the patient from lying in a side sleeping positionwith a side region of the patient's head on a pillow.

In one form of the present technology, a positioning and stabilisingstructure 9300 is provided with a decoupling portion located between ananterior portion of the positioning and stabilising structure 9300, anda posterior portion of the positioning and stabilising structure 9300.The decoupling portion does not resist compression and may be, e.g. aflexible or floppy strap. The decoupling portion is constructed andarranged so that when the patient lies with their head on a pillow, thepresence of the decoupling portion prevents a force on the posteriorportion from being transmitted along the positioning and stabilisingstructure 9300 and disrupting the seal.

In one form of the present technology, a positioning and stabilisingstructure 9300 comprises a strap constructed from a laminate of a fabricpatient-contacting layer, a foam inner layer and a fabric outer layer.In one form, the foam is porous to allow moisture, (e.g., sweat), topass through the strap. In one form, the fabric outer layer comprisesloop material to engage with a hook material portion. In one form,conduits 9900 for delivering air to the cushion assembly 9105 may alsomake up the positioning and stabilizing structure 9100.

In certain forms of the present technology, a positioning andstabilising structure 9300 comprises a strap that is extensible, e.g.resiliently extensible. For example the strap may be configured in useto be in tension, and to direct a force to draw a seal-forming structureinto sealing contact with a portion of a patient's face. In an examplethe strap may be configured as a tie.

In one form of the present technology, the positioning and stabilisingstructure may include a first tie (e.g., upper strap 9302 (FIG. 24 )),the first tie being constructed and arranged so that in use at least aportion of an inferior edge thereof passes superior to an otobasionsuperior of the patient's head.

In one form of the present technology suitable for a full-face mask, thepositioning and stabilising structure includes a second tie (e.g., lowerstrap 9303 (FIG. 24 )), the second tie being constructed and arranged sothat in use at least a portion of a superior edge thereof passesinferior to an otobasion inferior of the patient's head and overlays orlies inferior to the occipital bone of the patient's head.

In one form of the present technology suitable for a nasal-only mask orfor a full-face mask, the positioning and stabilising structure includesa third tie (e.g., strap connector 9304 (FIG. 22 )) that is constructedand arranged to interconnect the first tie and the second tie to reducea tendency of the first tie and the second tie to move apart from oneanother.

In certain forms of the present technology, a positioning andstabilising structure 9300 comprises a strap that is bendable and e.g.non-rigid. An advantage of this aspect is that the strap is morecomfortable for a patient to lie upon while the patient is sleeping.

In certain forms of the present technology, a positioning andstabilising structure 9300 comprises a strap constructed to bebreathable to allow moisture vapour to be transmitted through the strap,

In certain forms of the present technology, a system is providedcomprising more than one positioning and stabilizing structure 9300,each being configured to provide a retaining force to correspond to adifferent size and/or shape range. For example, the system may compriseone form of positioning and stabilizing structure 9300 suitable for alarge sized head, but not a small sized head, and another suitable for asmall sized head, but not a large sized head.

The positioning and stabilising structure 9300 may include a clip 9301to secure respective ties, e.g., to the conduit connectors 9800 as shownin FIG. 22 . The clip 9301 and the conduit connector 9800 may eachinclude a magnet arranged with opposing polarities to facilitate aconnection therebetween.

5.3.3.4 Vent

In one form, the patient interface 6000 includes a vent 6400 constructedand arranged to allow for the washout of exhaled gases, e.g. carbondioxide, as shown in FIG. 30 .

In certain forms, the vent 6400 is configured to allow a continuous ventflow from an interior of the plenum chamber 6200 to ambient whilst thepressure within the plenum chamber is positive with respect to ambient.The vent 6400 is configured such that the vent flow rate has a magnitudesufficient to reduce rebreathing of exhaled CO2 by the patient whilemaintaining the therapeutic pressure in the plenum chamber in use.

One form of vent 6400 in accordance with the present technologycomprises a plurality of holes, for example, about 20 to about 80 holes,or about 40 to about 60 holes, or about 45 to about 55 holes.

A vent 6400 may be located in the plenum chamber 6200. Alternatively, avent 9404 is located in a decoupling structure, e.g., a swivel (seee.g., FIG. 22 ).

The conduit connectors 6800, which are described in greater detailbelow, may also include vent features.

5.3.3.5 Decoupling Structure(s)

In one form, the patient interface 9000 includes at least one decouplingstructure, for example, a swivel or a ball and socket.

5.3.3.6 Connection Port

Connection port 6600 allows for connection to the tube 6348 of aircircuit 4170 (see e.g., FIG. 7 ). The connection port 9600 according toan example of the present technology may be connected to the connectionport housing 9903 (see e.g., FIG. 22 ). The connection port 9600 may beswivelable relative to the connection port housing 9903 and theconnection to the air circuit 4170 may also be swivelable.

The connection port 9600 and the connection port housing 9903 may bepositioned superior to the patient's head in use.

5.3.3.7 Forehead Support

Examples of the patient interfaces of the present technology shown inFIGS. 22-39 do not include a forehead support. Variations of the patientinterface of the present technology may include a forehead support.

5.3.3.8 Conduits

The patient interface 9000 according to examples of the presenttechnology may include conduits 9900 to provide the flow of pressurizedair from the connection port 9600 to the cavity 9001 in the plenumchamber 9200. The conduits 9900 may be similar to the lateral portions3302 and superior portions 3304 of FIG. 6 , and to the tube 6350 of FIG.7 . The conduits 9900 may be joined superior to the patient's head atthe connection port housing 9903 and may pass along lateral sides of thepatient's head between corresponding ones of the patient's eyes andears. The conduits 9900 may be connected to the cushion assembly 9105(e.g., plenum chamber 9200) via conduit connectors 9800, as describedbelow, to provide the flow of pressurized air to the cavity 9001.

The conduits 9900 may also stabilize and position the seal-formingstructure 9100 on the patient's face. Thus, the conduits 9900 mayfunction similarly to the ties of the positioning and stabilisingstructure 9300. Accordingly, the mechanical connection of the conduits9900 to the conduit connectors 9800 may be sufficient for tension forcesin the conduits 9900 to be transmitted to the seal-forming structure9100 through the conduit connectors 9800.

The conduits 9900 may include features of similar conduits disclosed inInternational Application Publication No. WO 2017/124155 A1, which ishereby incorporated by reference herein in its entirety. For example,the conduits 9900 of the present technology may include features of theheadgear tubes 3350 depicted in FIGS. 3A-3L of this document, as well asthe associated written description.

The conduits 9900 may also be provided with sleeves 9901 to cushion thepatient's face against the conduits 9900. The sleeves 9901 may beremovable. The sleeves 9901 may be made from a breathable material.

The conduits 9900 may also include tie connectors 9902 to facilitateconnection with ties of the positioning and stabilising structure 9300.

5.3.3.9 Conduit Connectors

As shown in FIGS. 26-33 , the patient interface 6000 may include severalviews of conduit connectors 6800 of the patient interface 6000,according to examples of the present technology. The conduit connectorsmay connect the conduits to the cushion assembly 6105 to provide theflow of pressurized air to the cavity 6001. These conduit connectors6800 may be similar to the conduit connectors 9800 (see e.g., FIGS.22-25 ), and the following description may equally apply to the conduitconnectors 9800.

The conduit connectors 6800 may each be formed with a conduit connectorhousing 6801. The conduit connectors 6800 may provide other functions,as described below, such as venting of the plenum chamber 6200,connection to the positioning and stabilising structure, and asphyxiaprevention by inclusion of an anti-asphyxia valve 6850.

In FIGS. 26-33 , the conduit connectors 6800 are shown attached to theplenum chamber 6200 at the plenum chamber holes (see e.g., similarplenum chamber holes 9210). As can be seen, there is one conduitconnector 6800 on each lateral side of the cushion assembly 6105, andeach conduit connector 6800 is connected to a plenum chamber hole oneach corresponding lateral side of the cushion assembly 6105. Theconduit connectors 6800 may each include a conduit connector attachmentstructure to connect each of the conduit connectors 6800 to a respectiveplenum chamber hole at the connection rim (not shown). The connectionmay be mechanical, e.g., snap-fit or friction fit. The connection mayalso be removable. The material of the conduit connectors 6800 and thematerial of the plenum chamber 6200 may each be selected to facilitatethe desired connection features. For example, the material of theconduit connectors 6800 and the material of the plenum chamber 6200 mayeach be relatively rigid to permit the audible and/or tactile feedbackassociated with a snap-fit. The material of the conduit connectors 6800and the material of the plenum chamber 6200 may be different in at leastone aspect or the materials may be the same. The conduit connectors 6800may also be permanently connected to the plenum chamber at the plenumchamber holes. For example, the conduit connectors 6800 may beultrasonically welded to the plenum chamber 6200. The connection betweenthe conduit connectors 6800 and the plenum chamber 6200, whetherremovable or permanent, may also be designed to be sufficiently strongsuch that tension from the conduits can be transferred to the plenumchamber 6200 without disrupting the connection because, as explainedabove, the conduit connectors 6800 may facilitate positioning andstabilising of the seal-forming structure 6100 on the patient's head.

The conduit connectors 6800 may also be attached to lateral sides of theplenum chamber 6200 to improve aesthetics of the patient interface 6000.As explained above, the plenum chamber 6200 may be constructed of atransparent or translucent material, which may allow visibility of thepatient's facial features. By locating the conduit connectors 6800laterally on the plenum chamber, e.g., as shown in the depictedexamples, more of the patient's face is visible, and that arrangementcan improve aesthetics of the patient interface 6000. This contrastswith alternative designs where an elbow and air circuit may be joined tothe center of the plenum chamber 6200, thereby obstructing the view ofthe patient's face.

The conduit connectors 6800 may also each include a conduit connectionend 6802 that connects to a respective conduit (e.g., similar to theconduit 9900 in FIG. 22 ). The connection between the conduits and theconduit connectors 6800 at the conduit connection ends 6802 may beremovable or permanent. A conduit connector inlet hole 6803 may beformed in the conduit connector housing 6801 at the conduit connectionend 6802 to receive the flow of pressurized air. The conduit connectors6800 may include structure, e.g., an undercut, to facilitate aremovable, snap-fit connection with corresponding conduits, and eachconduit may include a relatively rigid structure at the end thatconnects to the conduit connectors 6800 to facilitate such a connection.The conduit connectors 6800 may also be joined to the conduits with afriction fit, a snap-fit, or any similar fit. Again, as explained above,the conduits may provide a positioning and stabilising function tolocate the seal-forming structure in a therapeutically effective sealingposition on the patient's face, and therefore the connection between theconduits and the conduit connectors 6800 at the conduit connection ends6802 may be sufficiently secure to permit tension forces from theconduits to be transmitted to the conduit connectors 6800 withoutdisrupting the connection between the conduits and the conduitconnectors 6800 at the conduit connection ends 6802.

As shown in FIG. 29 , the conduit connectors 6800 may also provide aventing function for the patient interface 6000. The conduit connectorhousing 6801 may include a vent inlet that is in pneumatic communicationwith the cavity 6001 when the patient interface 6000 is assembled. Theconduit connector housing 6801 may also include at least one conduitconnector vent hole 6831. As can be seen in the depicted examples, eachconduit connector housing 6801 includes a plurality of conduit connectorvent holes 6831. This ensures adequate mixing of newly introduced airand air already present in the plenum chamber 6200, which can enhancecarbon dioxide washout and increase the amount of fresh air provided tothe patient for respiration.

As shown in FIG. 22-24 , the similar conduit connectors 9800 may alsoprovide a connection to ties of the positioning and stabilisingstructure 9300. The inferior ties may be joined to the conduitconnectors 9800 with clips 9301. The clips 9301 and the conduitconnectors 9800 may include magnets with opposing polarities tofacilitate the connection. The connection between the ties of thepositioning and stabilising structure 9300 and the conduit connectors9800 may be releasable. The tension from the inferior ties of thepositioning and stabilising structure 9300 may urge inferior portions ofthe seal-forming structure 9100 into sealing engagement with thepatient's face, e.g., around the mouth. Alternatively, structure toconnect to the clips 9301 may be formed directly on a conduit connectorhousing.

5.3.3.10 Anti-Asphyxia Valve

In one form, the patient interface 6000 includes an anti-asphyxia valve.As best shown in FIGS. 30 and 31 , each of the conduit connectors 6800may include an anti-asphyxia valve assembly 6850. Accordingly, thepatient interface 6000 may include two anti-asphyxia valve assemblies6850. Each of the anti-asphyxia valve assemblies 6850 may operateindependent of the other, i.e., in response to a cessation of the flowof pressurized air. For example, if the patient is sleeping on his orher side when there is a cessation of the flow of pressurized air andone of the anti-asphyxia valve assemblies 6850 is occluded, e.g., by apillow, the other of the anti-asphyxia valve assemblies 6850 canfunction to prevent the patient from being asphyxiated. Although notexplicitly shown, the patient interfaces of FIGS. 22 to 25 and 33-1 to39 may also include at least one anti-asphyxia valve.

5.3.3.11 Ports

In one form of the present technology, a patient interface 6000 includesone or more ports that allow access to the volume within the plenumchamber 6200. In one form this allows a clinician to supply supplementaloxygen. In one form, this allows for the direct measurement of aproperty of gases within the plenum chamber 6200, such as the pressure.Although not explicitly shown, the patient interfaces of FIGS. 22 to 25and 33-1 to 39 may also include at least one port.

5.3.4 Support Structure and Sealing Portion Arrangements

The support structures and sealing portions in the examples describedabove may have a number of different configurations and arrangements.

In use, the sealing portion 3130 (e.g., textile membrane) may bemaintained in sealing contact with the patient's face by 1) a reactivestress of the support structure 3120; 2) a pre-formed state of thetextile membrane 3130 formed as a non-tensioned, yet substantiallyconstant surface, without leak causing interruptions such as creases,folds, buckles or wrinkles in the textile membrane 3130; and/or 3) airpressure within the cavity against an inside surface of the sealingportion 3130. Each of these factors may contribute to the sealingportion 3130 complying with the anthropometric contours of the patient'sface, thereby minimizing wrinkles or blow-out and maximizing the contactarea of the sealing portion 3130. Tension in the sealing portion 3130may increase as a result of any of these factors, but the sealingportion 3130 may return to a relaxed state with the removal of theassociated factor.

In some examples, the sealing portion 3130 may comprise a relativelythin, compliant, stretchable, elastic material, such as a textilemembrane comprising a suitable textile material (e.g., nylon, polyester,nylon and polyester mix, microfiber or polyurethane). The sealingportion 3130 may be molded or otherwise attached (e.g., adhered, glued)to the support structure 3120 so that there are no wrinkles in thematerial of the sealing portion 3130. This may be advantageous inensuring that the sealing portion forms a smooth and continuous seal onthe patient's face without any folded sections through which air mayleak. Further, the sealing portion 3130 may be shaped or have curvatureimparted thereto. The support structure 3120 may also impart curvatureto the sealing portion 3130. In the illustrated examples, the sealingportion 3130 may include curvatures about multiple axes. This may assistthe sealing portion 3130 in contouring to the complex facial structureof different patients.

For example, as shown in FIGS. 12-21 the sealing portion 3130 may have aconcave curved profile from one lateral side (right) to an opposinglateral side (left) (e.g., positive domed curvature in a left-rightdirection) in order to cradle the patient's nose while the patientinterface 3000 is being worn. In other words, the curvature of thesealing portion 3130 is positive relative to a location where thepatient's columella and/or subnasale contact the sealing portion 3130.

In some forms, as shown for example in FIGS. 11-39 , the patient's noseis not intended to be received in the cavity 3101 formed by the plenumchamber 3200 and the seal-forming structure 3100. Instead, unlikeconventional masks, the patient's nose is intended to press against thetextile membrane 3130 which in turn accommodates the contours of thepatient's face to comfortably form a reliable seal with the patient'sairways. The textile membrane 3130 may stretch to accommodate thepatient's face. Specifically, the textile membrane 3130 in FIGS. 11-21and the textile membranes in FIGS. 31-1 to 39 may be held in arelatively relaxed (i.e., un-tensioned) state prior to contact with thepatient. As the patient contacts the textile membrane 3130 (e.g., viatheir nose), the seal-forming structure 3100 forms to the patient's face(e.g., their nose) as a result of the compliant, stretchy nature. Inother words, contact with the patient's face applies tension to thetextile membrane 3130, and causes it to form a complimentary shape tothe patient's nose. The slack in the initial form of the seal-formingstructure 3100 may allow better contouring to a patient's face than ifthe seal-forming structure 3100 was initially under tension, becausethere are fewer locations resistant to changing shape. Some examplesinclude the bridge portion 3104 that may function to help provide, byeliminating a central opening in the textile membrane 3130, a sealingportion that presses against the patient's nose rather than receives thepatient's nose in the cavity 3101. The bridge portion 3104 may create alocation where the patient may apply tension to the textile membrane3130 so that the seal-forming structure 3100 is snug and/or tightagainst the patient's facial features (e.g., in order to limit and/orprevent leaks). This also creates a different sealing experience ascompared to conventional masks. This sealing experience may provideenhanced comfort due to contact with a compliant textile membrane 3130rather than the more rigid materials of conventional masks orconventional sealing arrangements where the sealing portion 3130 has asmaller contact area around a perimeter of the nose and/or mouth. Thebridge portion 3104 (or any area selectively tensioned) may create alocation where the patient may apply tension to the textile membrane3130 regardless of whether the bridge portion 3104 is located near atleast one hole.

The textile membranes 6130 (e.g., the first sealing portion 6131) may beheld in a relatively tensed state prior to contact with the patient(e.g., the first sealing portion 6131 may be under continuous tension).As the patient contacts the textile membrane 6130 (e.g., via theirnose), the seal-forming structure 6100 forms to the patient's face(e.g., their nose) as a result of the compliant, stretchy nature. Inother words, contact with the patient's face applies additional tensionto the textile membrane 6130, and causes it to form a complimentaryshape to the patient's nose. The entire first sealing portion 6131 mayact in a manner similar to the bridge portion 3104 described above,because it may create a location where the patient may apply tension tothe textile membrane 6130 so that the seal-forming structure 6100 issnug and/or tight against the patient's facial features (e.g., in orderto limit and/or prevent leaks). While the textile membrane 6130 is taut,the material may be sufficiently complaint or stretchy so that thematerial can conform to the patient's facial features with theapplication of additional tension. The pre-tension in the first sealingportion 6131, combined with the pressurized seal resulting from the flowof pressurized air, may create a more robust seal in comparison havingonly pressurized seal resulting from the flow of pressurized air (e.g.,as in the patient interfaces 3000, 9000, 21000, 23000, 25000).

Compared to conventional silicone membranes and compression foam seals,the sealing portion 3130 in some of the present examples has a moreflexible structural stiffness and therefore has a dynamic spring backcharacteristic that enables the sealing portion 3130 to recover morequickly when disturbed by an external force. Further, due to the lowerstructural stiffness a smaller seal force is required allowing thesealing portion 3130 to be more comfortable and create less facial marksduring use.

The textile membrane 3130 may exhibit variable tension forces across thematerial (e.g., less tension forces proximal to the naris openings 3102or in wider stretches of material). The textile membrane 6130 may alsobe under less tension proximal to the naris openings 6103 since thecentral portion of the textile membrane 6130 may be unsupported andslightly slacked compared to the perimeter of the textile membrane 6130.In some forms, the surface of the material of the sealing portion (e.g.,3130) that contacts the patient's face may have low frictioncharacteristics (e.g., a low friction finish), which may advantageouslyimprove compliance of the material with the patient's face while alsoimproving patient comfort.

The textile membrane 3130 may exhibit variable tension forces across thematerial (e.g., greater tension forces proximal to the bridge portion3104). The textile membranes 9130, 21130, 23130, 21530 may exhibitsimilar variable tension forces. In some forms, the surface of thematerial of the textile membrane 3130 that contacts the patient's facemay have low friction characteristics (e.g., a low friction finish),which may advantageously improve compliance of the material with thepatient's face while also improving patient comfort.

In some examples, underlying cushion layer(s) (e.g., portion or secondwall 3126) may assist in optimizing the sealing portion 3130 contactsurface area with the patient's face. Further, in examples where thesealing portion 3130 is constructed from a breathable material (e.g., abreathable textile), the underlying cushion layer(s) may providesufficient contact area behind the sealing portion to adequately sealthe sealing portion against the patient's face and prevent leakage.

The underlying cushion layer(s) may provide additional flexibility andallow the cushion to be suitable for use by most patient faces (e.g.,one size fits most). For example, the sealing portion may be structuredas a double air assisted sealing portion (e.g., dual textile membranes),a sealing portion with compression support layer(s) (e.g., open cellfoam, polyurethane foam, gel), a sealing portion with TPU, TPE orsilicone support layer(s), or a double air assisted sealing portion withadditional support layer(s) (e.g., dual textile membranes wherein theinner membrane has a foam laminate layer (e.g., open cell, polyurethane)or a TPU, TPE, polyurethane or silicone molded layer thereon).

In use, engagement of the patient's face 1000 with the sealing portion10130 will create a temporary strain force that attempts to pull thewalls of the support structure 10120 toward one another, as shown inFIG. 43 . The support structure 10120 will respond to the strain forcewith an outwardly pulling reaction force. The reaction force transfersmore tension to the sealing portion 10130 by preferentially stretchingthe more compliant sealing portion which creates a resultant springforce in the sealing portion that is exerted on the patient's face.

The sealing portion 10130 may be integrated with the support structureby molding or otherwise attaching the sealing portion 10130 to the inneredge of the support structure 10120. Thus, for example, an outerperimeter of the sealing portion 10130 may be attached to the inner edgeof the support structure 10120 such that the sealing portion 10130extends radially inwardly of the seal-forming structure beyond or to afurther extent than the support structure 10120. The inner edge of thesupport structure 10120 may be curved such that the sealing portion10130 may be slightly angled inwardly toward the mask interior. Byattaching the sealing portion 10130 along the inner edge of the supportstructure 10120, the sealing portion 10130 does not need to be folded orcut to blend around the corners of the support structure 10120. This mayadvantageously reduce the occurrence of protruding folds or wrinkles inthe sealing portion 10130, which may cause leakage, thereby improvingthe performance of the seal.

5.3.4.1 Textile Membrane

In accordance with an example of the disclosed technology, thesealing-forming structure 3100 may include a textile membrane 3130comprising a textile material (see e.g., 10133). The textile materialmay have an airtight membrane/film or layer coated or otherwise appliedthereto to create an air-holding textile composite. The textilecomposite may be cut (e.g., die cut, ultrasonic, laser, or RF) to adesired shape and then attached to the support structure 3120. Theresulting textile sealing portion 3130 (or textile membrane) may beattached to the support structure 3120 (e.g., silicone, TPE), forexample, by overmolding or injection molding. In another example, thetextile sealing portion 3130 may be thermo-welded at its edges (outerperimeter) onto the material of the support structure 3120 (e.g.,silicone, TPE). In another example, the textile sealing portion 3130 maynot be coupled to a support structure 3120, and the cushion interface3105 may be constructed substantially from a textile material.

In an example, the textile material 10133 is a stretch textile. This mayinclude a knitted material, a woven material, or any other suitablematerial. A knitted material may be preferable as it provides thetextile with elasticity (e.g., stretchiness), particularly in comparisonwith woven materials. This may be advantageous in providing comfort tothe patient, as described below. The elasticity may be in all directions(e.g., four-way stretch/elasticity, e.g., substantially equal elasticityin all directions), and at least in the lateral left-right direction ofthe textile membrane. The textile material may have a weft knitstructure or a warp knit structure, for example. The textile material10133 may also be any other suitable knit structure. A weft knitstructure may be more desirable as the elasticity of weft knit textilesis higher than the elasticity of warp knit textiles.

FIG. 45 illustrates the wale 70 of a weft knit fabric, or the directionthat the loops of one thread join to a loop of another thread. Thecourse 80, or the direction of the loops from a single thread is shownin FIG. 46 . FIG. 47 illustrates a basic closed loop warp knit 90 inwhich the wales and courses running parallel to one another. FIG. 48illustrates a weft knit 100 in which the wales 70 run perpendicular tothe course 80.

5.3.4.1.1 Manufacturing

The human face includes a variety of contours, which may be described aseither positive or negative curvatures, and either dome or saddleregions. In order to provide increased comfort to a patient, theseal-forming structure 3100 ideally matches or substantially matches thecontours. As described above however, the seal-forming structure 3100should be smooth and continuous on the patient's face without any foldedsections through which air may leak. Thus, a complex geometry of theseal-forming structure 3100 needs to be formed with multiple curvaturesto compliment the patient's face, without creating a surface that issusceptible to leaks.

As shown in FIG. 49 , a textile material (e.g., the textile membrane3130) can be folded about a single axis 11000 (e.g., a horizontal axisas viewed in FIG. 49 ). In this state, the textile material 3130 has anegative domed curvature (e.g., is substantially convex) as viewed inFIG. 49 . The textile material 3130 is substantially smooth in thisorientation (e.g., the curvature has a constant radius R). In otherwords, the textile material 3130 is substantially free of wrinklesand/or creases while oriented with a fold about a single axis 11000.This would remain true regardless of which axis the textile material3130 was folded about, or in which direction. In other words, thetextile material 3130 could be folded about a vertical axis (i.e.,instead of a horizontal axis) and/or could have a positive domedcurvature (i.e., instead of a negative curvature), and the surface ofthe textile material 3130 would remain substantially free from wrinklesand/or creases. Additionally, altering the magnitude of curvature wouldnot create wrinkles and/or creases in the textile material. In otherwords, the singular fold in the textile material can include either alarge radius of curvature or a small radius of curvature withoutcreating wrinkles and/or creases in the textile material. Thus,different positive and negative curvatures (e.g., as illustrated inFIGS. 3B-3C and 3E-3F) could be applied to a textile material withoutcreating wrinkles and/or creases.

In order to compliment the complex surface orientations of a patient(and the differences between individual patients), a seal-formingstructure 3100 with multiple folds is more desirable in order to providemore contact with the patient's face. These curves are ideally aboutdifferent, non-parallel axes, since the curvatures on a patient's faceare about a variety of axes oriented in multiple directions. However, asshown in FIG. 50 , providing an additional (e.g., a second, third,fourth, etc.) fold to the textile material may create a wrinkle and/orcrease. The creases and/or wrinkles may arise when two or more folds areproduced along non-parallel axes 11000, 11500. In other words, multiplefolds all along parallel axes may not produce wrinkles and/or creases,but would also not produce a three-dimensional shape optimal for sealingwith a patient's face (e.g., because it would not match the patient'sfacial contours). By including curvatures along non-parallel axes, thesurface may no longer be maintained as smooth and continuous. Thus, anyseal-forming structure 3100 created from a textile with two or morefolds would be unlikely to effectively seal against a patient's face.

One way to effectively create curvatures in a material along multiple,non-parallel axes is to apply tension to at least a portion of thetextile material 3130. The application of tension may assist inmaintaining the shapes of the various curvatures, while also limitingand/or preventing the formation of creases and/or wrinkles.

One way to apply the tension is to stretch the textile material 3130,and impart multiple curvatures (e.g., along multiple, non-parallel axes)on the textile material while it is under tension. Then, the textilematerial 3130 can undergo a process (e.g., thermoforming), so that thetextile material 3130 can be permanently held in its distorted state(i.e., with its multiple curvatures). As shown in FIG. 51 , the textilematerial 3130 includes multiple curvatures, and its surface remainsrelatively smooth. Thus, this textile material 3130 could beincorporated into a patient interface 3000 as a seal-forming structure3100, and provide a seal with a patient's face, without substantiallyany leaks of pressurized air from the plenum chamber 3200 to theambient. In this example, substantially the entire textile material 3130is under tension.

However, once the textile material 3130 is stretched and thermoformed(or a similar process is applied), the textile material 3130substantially loses its free-state properties. For example, theelasticity that the textile material 3130 may naturally have, would besubstantially lost after the thermoforming was completed. A oncestretchy textile material 3130 would become relatively stiff whileincluding multiple curvature. A textile material's 3130 free-state(i.e., before being thermoformed) properties (e.g., drape, flexibility,elasticity, etc.) are also important in determining the sealingcapabilities of the eventual textile seal-forming structure 3100. Thus,if the textile material 3130 is no longer in its free-state, the qualityof the seal produced by the textile material 3130 may also be reducedfor some patients. In other words, while the curved textile material3130 formed using thermoforming may be more comfortable in conforming toa patient's face (e.g., as compared to a textile membrane 3130 formedwith only a single bend), the loss of its free state properties maydisrupt the ability for the patient interface 3000 to effectively sealwith some patient's faces. Even though there may be no wrinkles and/orcreases, a seal-forming structure 3100 formed in this way may stillallow leaks (e.g., because the textile membrane 3130 is too stiff toconform to some patient's faces). Other patients may experience a sealsufficient to prevent leaks.

This is not the case in the textile material 6130 of FIGS. 26-33 becausethe material may still include its free-state properties. Since thefirst sealing portion 6131 is intended to be substantially flat prior touse, the material does not need to be thermoformed in order to keep itsshape. The material may still stretch and conform to a patient's face.Thus, the textile material 6130 may be able to limit leaks, unlike theexample described above. The patient interface 6000 may also be easierto manufacture since the textile material 6130 may not include complexcurvatures.

FIGS. 52-61 show another way to apply tension to only a portion of thetextile membrane 3130. For example, less than half of the textilemembrane 3130 may be under tension, while the remained of the textilemembrane 3130 may be loose or slack. Thus, the tension is selectivelyapplied to discrete locations of the textile membrane 3130. Differentlocations (e.g., a central portion, side portions, etc.) of the textilemembrane 3130 may be tensioned in order to assist in impartingdifferently shaped curvatures. Additionally, more than one location maybe under tension in a single textile membrane 3130. Tension may beselectively applied to the textile membrane 3130 using any number oftechniques, some of which are described below.

One example technique of selectively applying tension to only a portionof the textile membrane 3130 may be accomplished by applying a crimp toa portion of the textile membrane 3130. The crimp may apply localizedtension without causing the entire textile membrane 3130 to be undertension. The crimp may be applied to any portion or portions of thetextile membrane 3130. In some examples, the majority of the textilemembrane 3130 is not imparted with a crimp. In other words, the area ofthe textile membrane 3130 that is crimped is less than the area of thetextile membrane 3130 that is not crimped. In some examples, sections ofthe textile material 3130 may be removed on at least one side of thecrimped portion. In some examples, holes or other discontinuities arenot needed in order to form the crimped portion.

In some examples, the crimp may be applied to a central portion of thetextile membrane 3130. Applying the crimp may be accomplished byremoving sections of the textile material 3130 (e.g., in order to formholes 3102) while the textile is in its free state (i.e., has not bethermoformed). The textile material 3130 can then be manipulated aroundthe created holes 3102 in order to limit the formation of any wrinklesand/or creases. These holes 3102 may be used later as the narisopenings, through which pressurized air may be delivered to thepatient's nares.

As shown in FIG. 52 , a textile material 3130 for use in a nasal onlypatient interface 3000 is shown. Two holes 3102 cut into the textilematerial (e.g., by hand, with a laser, etc.), with each hole 3102corresponding to a single naris of a patient. However, any number ofholes 3102 may be cut depending on the final use of the textile material(e.g., a single opening for both nares, an additional opening for themouth, etc.). These holes 3102 may be cut into the textile material 3130either before the first fold is made or after the first fold is made.The order of forming a single (i.e., first) fold and cutting will notsubstantially effect the presence of creases and/or wrinkles.

With specific reference to the textile material for use in a nasal onlymask as shown in FIG. 52 , each of the holes 3102 is elongated, andformed as a generally rectangular shape, although other shapes (e.g.,circular, triangular, etc.) may be used in other examples. The holes3102 may be separated by a strip of material that may be formed as abridge portion 3104. Although the bridge portion 3104 may also be formedindependently of the holes 3102. If more than two holes 3102 are cutinto the textile material 3130, there may be multiple bridge portions3104. Creating more bridge portions 3104 may be useful when additionalholes are needed, and/or if the textile material 3130 is larger (e.g.,so that it does not buckle despite a single bridge portion 3104). Asdescribed above, the patient's nose (e.g., their pronasale) may contactthe bridge portion 3104, and the bridge portion 3104 may limit thepatient's nose from extending into the plenum chamber 3200.

As shown in FIG. 53 , once the initial fold is made about a first axis11000 (e.g., a horizontal axis as shown in FIG. 53 ) and the holes 3102have been cut, the bridge portion 3104 may be folded (e.g., a secondfold) about a second axis 12000 that is parallel to (or collinear with)the first axis 11000. In the illustrated example, the bridge portion3104 is flipped into a downward direction (as viewed in FIG. 53 ) inorder to clear a space between the pair of holes 3102. In other words, apositive domed curvature (e.g., as viewed in FIG. 53 ) is imparted onthe bridge portion 3104, while the first fold was a negative domedcurvature.

In some forms, once the bridge portion 3104 is folded, a space 3180 iscreated between the holes 3102. Specifically, the holes 3102 may bevertically oriented (e.g., as viewed in FIG. 53 ) and the space 3180 isoriented along the first axis 11000. In other words, each of the holes3102 are substantially perpendicular to the first axis 11000, and thespace 3180 exists between openings to each of the holes 3102. A width ofthe space 3180 substantially corresponds to a width between the nasalalas or alar ridges of the patient. In other word, the width of thespace 3180 is large enough to receive a patient's nose, and have thepatient's nares approximately aligned with the holes. Apexes of thetextile material 3130 (i.e., created by the first fold) would contactthe patient proximate to the nasolabial sulcus when the nose ispositioned within the space.

As shown in FIG. 54 , once the bridge portion 3104 has been folded aboutthe second axis 12000, the material may be crimped in order to maintainits “flipped” orientation. Crimping may be one way to selectively applytension to a portion of the textile membrane 3130, without applyingtension to the entire textile membrane 3130. Other techniques ofselectively applying tension may similarly be incorporated either withor instead of crimping. The bridge portion 3104 is maintained so as tono longer have the first curvature 10000 about the first axis 11000. Forexample, the bridge portion 3104 may not have an explicitly positivedomed curvature (e.g., the bridge portion 3104 may have a smallermagnitude of curvature in FIG. 54 than in FIG. 53 , the bridge portion3104 may have a zero curvature, etc.), but would not have a negativedome curvature along with the remainder of the textile material 3130(e.g., while the cushion assembly 3105 is in use). In other words, afterthe crimping occurs, the curvature in the bridge portion 3104 isdifferent (e.g., in magnitude and/or direction) than the rest of thetextile material 3130.

In some examples, the bridge portion 3104 is crimped so that thematerial forming the bridge portion alone is taut (i.e., crimping maynot apply tension to the rest of the textile membrane 3130).Specifically, a length of the bridge portion 3104 is folded againstitself in order to reduce a total exposed length. The tension in thetextile that comprises the crimped bridge portion 3104 is greater thanthe tension in the surrounding textile, which has not been crimped.Thus, a surface of the bridge portion 3104 may be substantially flatand/or may have minimal curvature (e.g., while the curvature about thefirst axis 11000 remains through the rest of the textile material 3130).The fold in the bridge portion 3104 may be substantially in the center,so that a length of material on either side of the fold line issubstantially equal, although one side may be longer than the other.Although the crimp creates tension, the bridge portion 3104 may still beable to flex relative to the holes 3102 (e.g., as a result of thefree-state properties of the textile). The crimped bridge portion 3104may be similar to the un-crimped bridge portion 6106 since both areunder tension, but also retain their free-state material properties.

In other examples, other ways of applying tension may be used to createa taut bridge portion 3104, and/or tension may be applied to otherlocations of the textile membrane 3130.

In some examples, the resulting length of the bridge portion 3104 afterbeing crimped affects the size of the holes 3102. For example, if theusable length remains large (i.e., the crimped length is small), theholes 3102 remain large. Said another way, there is a directrelationship between the length of the bridge portion 3104 that iscrimped and the size of the holes 3102. When the length of the bridgeportion 3104 decreases (i.e., because the crimped length increases), thetension in the crimped bridge portion reduces the size (e.g., thecircumference) of each hole 3102. The length of the bridge portion 3104may be adjusted based on a size of the patient's nose (e.g., the bridgeportion 3104 may be crimped with small, medium, and large sizes in orderto accommodate different sized nares).

In some examples, the bridge portion 3104 is maintained in its crimpedstate as a result of ultrasonic welding and/or applying an adhesive(e.g., glue), although any suitable method may be used. Any of thesemethods may be applied to the non-usable length 3184 of the bridgeportion 3104. For example, an adhesive may be applied to a selectedportion of the textile layer of textile membrane 3130, and the selectedportions are folded against one another. In other words, the useablelength of the bridge portion 3104 may be substantially free from anysubstance that was applied. The crimped region of the bridge portion3104 may still have the positive domed curvature described above, evenafter one of the securing methods has been applied.

In one example, a portion of the non-usable portion 3184 of the bridgeportion 3104 may be trimmed or cut after the securing method is applied.Once the textile membrane 3130 is completely assembled as a seal-formingstructure 3100, the non-usable portion 3184 would be positioned withinthe plenum chamber 3200, and may cause a disruption to airflow (e.g.,and create noise). Thus, trimming the non-usable portion 3184 may reduceor eliminate any disturbances.

As shown in FIGS. 55-57 , once the crimping is complete, additionalcurvatures about different axes may be applied to the textile material3130. Crimping the bridge portion 3104 may reduce the total area 3188that is affected by additional curvatures. Said another way, theaffected area 3188 (i.e., shown in hatching) with the bridge portion3104 crimped in FIG. 55 is less than the affected area 3190 in FIG. 51where crimping has not occurred. The affected area 3188, 3190 relates tothe area where creases and/or wrinkles are likely to appear as a resultof introducing multiple curvatures to the textile material 3130. Whenthe bridge portion 3104 is crimped, the affected area 3188 issubstantially close to the holes 3102. For example, the affected area3188 may form a substantially rectangular shape, with edgessubstantially tangent to the holes 3102. The close proximity of theaffected area 3188 to the holes 3102 substantially prevents creasesand/or wrinkles from forming when additional curvatures are applied tothe textile material 3130.

In some examples, a third curvature 30000 is formed in the textilematerial 3130 about a third axis 13000. The third axis may extend alonga direction substantially perpendicular to the first and second axes11000, 12000 (although it could also be oblique or skew). In otherwords, the third axis 13000 may be a substantially horizontal axis(e.g., as viewed in FIGS. 55-57 ). In the illustrated example, the thirdaxis 13000 is centered on the textile material 3130, and extends alongthe bridge portion 3104. The third curvature 30000 may have asubstantially saddle region (e.g., as viewed in FIGS. 55-57 ). In otherwords, the third curvature 30000 may be positively curved and may cradlethe patient's nose after the patient dons the patient interface 3000.This means that the textile layer 10133 specifically is a saddle regionabout the third axis 13000 when the patient interface 3000 is worn.Thus, the second and third curvatures 20000, 30000 may curve in the samedirection (e.g., both positive curvatures), although about substantiallyperpendicular axes and may define different regions (e.g., the secondcurvature 20000 is a dome and the third curvature 30000 is a saddle).While the third curvature 30000 is applied, the first and secondcurvatures 10000, 20000 remain in their previously curved position. Inother words, the application of the third curvature 30000 (or additionalcurvatures) may not substantially affect the magnitude and/or directionof the previous curvatures.

In some examples, a fourth curvature 40000 may be formed in the textilematerial 3130 about a fourth axis 14000, which may extend along adirection substantially perpendicular to the first, second, and thirdaxes 11000, 12000, 13000 (although the fourth axis 14000 may have anyrelationship to the other axes). In other words, the fourth axis 14000may be a substantially vertical axis (e.g., as viewed in FIG. 55 ). Inthe illustrated example, the fourth axis 14000 does not intersect thebridge portion 3104. The fourth curvature 40000 may extend toward acenter of the textile material 3130, and may be a saddle region asviewed in FIG. 55 . In other words, the fourth curvature 40000 maycradle the patient's face (e.g., their lip superior) after the patientdons the patient interface 3000.

In some examples, the fifth curvature 50000 may be formed in the textilematerial 3130 about a fifth axis 15000, which extends along a directionsubstantially parallel to, and offset from, the first and second axes11000, 12000 (although the fifth axis 15000 may have any orientation).In other words, the fifth axis 15000 is a substantially horizontal axis(e.g., as viewed in FIG. 56 ). In the illustrated example, the fifthaxis 15000 does not intersect the bridge portion 3104. The fifthcurvature 50000 includes a similar orientation as the first curvature10000, and may be a negative dome curvature (e.g., as viewed in FIG. 56). The first and fifth curvatures 10000, 50000 may have differentmagnitudes of curvature (e.g., the magnitude of the first curvature10000 may be more negative than that of the fifth curvature 50000). Thefifth curvature 50000 may have a variable curvature, in that its radiusof curvature may not be constant along the length of the axis 15000. Forexample, since the fifth curvature 50000 and the first curvature 10000are along substantially parallel axes, changing the radius of curvatureof the fifth curvature 50000 may bring the two curvatures 10000, 50000together (e.g., blend them into one curvature). The fifth curvature50000 may have a smaller radius of curvature proximate its center (e.g.,proximate to an intersection with the third axis 13000), and has alarger radius of curvature proximate an edge of the textile material3130. Here, the larger radius of curvature of the fifth curvature 50000may blend into the first curvature 10000 (e.g., proximate to an edge ofthe textile material 3130). In other words, fifth curvature 50000 mayextend into the first curvature 10000 as the radius of curvature in thefifth curvature 50000 increases. Blending the curvatures may assist inproviding a smooth surface, and limiting the potential of formingcreases and/or wrinkles in the bent textile material 3130.

In some examples, the fourth and fifth curvatures 40000, 50000 are bothincluded on the textile material 3130. In other words, the medialsubnasale region 3260 of the eventual seal-forming structure 3100constructed from the textile material 3130 may include both the fourthcurvature 40000 and the fifth curvature 50000. These curvatures 40000,50000 may work together to seal against the compound curvature (e.g.,multiple curvatures in multiple directions) on a patient's lip superior.In the illustrated example, the fourth curvature 40000 is the dominatecurvature of the medial subnasale region 3260 when both the fourth andfifth curvatures 40000, 50000 are included on the textile material 3130.For example, the human head has a natural curvature toward eitherlateral side. In other words, the lip superior curves to the left andright sides of the patient's face, from the philtrum and toward thecheilion. The lip superior may also include a curvature about asubstantially horizontal axis, which runs perpendicular to the sagittalplane. However, this curvature is over a smaller distance (i.e., thedistance between the subnasale and the upper vermillion is less than themouth width), and may have more variance among different patients (e.g.,some may have a larger, more defined curve than others).

The fourth curvature 40000 would be the larger curvature, as compared tothe fifth curvature 50000. This may include the textile material 3130extending around the fourth axis 14000, and a lower edge of the textilematerial 3130 being folded about the fifth axis 15000, so that thefourth curvature 40000 includes more total area on the textile material3130. However, the crimped bridge portion 3104 allows both curvatures40000, 50000 to be maintained in an overlapping region without formingcreases and/or wrinkles. Thus, in some examples, the fifth curvature50000 may not be entirely along the fifth axis 15000, and may insteadextend along a curved path as it follows the length of the fourthcurvature 40000.

Some patients may have a substantially vertical lip superior between thesubnasale and the upper vermillion, and thus there may be substantiallyno curvature along the substantially horizontal axis perpendicular tothe sagittal plane. In these patients, the fifth curvature 50000 may notinclude a curved lip region to seal against. However, the material ofthe fifth curvature 50000 may deform into the substantially vertical(e.g., flat) region, and is still capable of maintaining an effectiveseal against the patient's face. Additionally, the height between thesubnasale and the upper vermillion may be different on differentpatients. For example, this distance may be very small. In this example,the textile material of the fifth curvature 50000 may be able to deforminto the tight region and work as a lead in, in order to effectivelyseal against any height. In other examples, the textile material may becustomizable for individual patients, and the curvatures, as well asradii of curvature, are selected based on a particular patient's facialgeometry (e.g., which may be identified using scanning).

Any number of these curvatures may be applied to a single seal-formingstructure 3100 in order to assist in enhancing the fit of the patientinterface 3000 against the patient's face. For example, all five ofthese curvatures may be applied to a single seal-forming structure 3100.In other examples, only some of the curvatures may be applied to theseal-forming structure 3100. In other examples, more than fivecurvatures may be applied to the seal-forming structure 3100. Themagnitude and/or directions of the curvatures may be variable acrossindividual cushion assemblies 3105 (e.g., the textile membrane 3130 maybe custom made for an individual patient).

In some examples, the shape of the textile membrane 3130 may be formed,and the textile membrane 3130 may be connected to the lateral supportregion 3122. In the illustrated example, the textile membrane 3130 andthe lateral support region 3122 are connected using injection molding sothat they are formed integrally with one another. In other examples, thetextile membrane 3130 and the lateral support region 3122 may be coupledtogether in a different way (e.g., by overmolding). In still otherexamples, the textile membrane 3130 may not be coupled to a lateralsupport region 3122.

In some examples, the three-dimensional shape (i.e., resulting from themultiple curvatures) of the textile membrane 3130 may assist aninjection molding tool in forming the flexible support structure 3120and/or the plenum chamber 3200. For example, the bridge portion 3104folded about the second axis 12000 (e.g., and crimped) may be usefulwhen loading the textile membrane 3130 into the injection molding tool.Specifically, the crimped bridge portion 3104 may be used as a spigotwhen placing the textile membrane 3130 in the injection molding tool. Inother examples, the textile material 3130 may be curved in order tocompletely form the plenum chamber 3200, such that an injection moldedmaterial is not needed in the patient interface 3000. In other words,the plenum chamber 3200 and seal-forming structure 3100 may beconstructed from the textile material 3130, and not from silicone, orother flexible, molded material.

As shown in FIGS. 58 and 59 , a material (e.g., silicone) may be moldedonto the textile membrane 3130. The material may be applied to the innerlayer 3194 of the textile membrane 3130 (e.g., the layer coated with anair impermeable material 10131), so as to avoid covering a portion ofthe textile on the posterior surface (and potentially contact thepatient's face, in use). Although, in other examples, the material maybe applied to the outer layer 3196 of the textile membrane 3130. Thematerial may extend beyond an end of the textile membrane 3130 andtoward the plenum chamber 3200 (e.g., the material may be molded so thatsome of the lateral support region 3122 does not contact the textilemembrane 3130). As the material is molded to the textile membrane 3130,the resulting support structure 3120 may have substantially the samecurvature (i.e., magnitude and direction) as the adjacent textilemembrane 3130 (e.g., in order to create a substantially smooth, anduninterrupted surface). The thickness of the material (i.e., the lateralsupport region) may change along its length. For example, the lateralsupport region 3122 may be thicker distal to the textile membrane 3130.Additionally, a total thickness of the overlapping textile membrane andmaterial may also be thinner than the adjacent region containing onlythe molded material (i.e., the lateral support region 3122).

As shown in FIG. 58 , some examples of the patient interface 3000 mayinclude a single wall lateral support region coupled to the textilemembrane 3130. A single wall of silicone material may be molded to thetextile membrane 3130, in order to form the support structure 3120 thatconnects the seal-forming structure 3100 to the plenum chamber 3200. Anouter surface 3195 of the support structure 3120 substantially matchesthe outer surface 3196 of the textile membrane 3130 (i.e., the textilelayer), in order to form a smooth, continuous surface. The inner surface3197 may have a different thickness as described above. The siliconematerial overlaps a portion of the textile membrane 3130 in order toform a sturdy connection, but not add unnecessary weight to the patientinterface 3000. The silicone material may taper to its smallestthickness at an end of the overlap region 3199 (e.g., proximate to end3124). The end of the overlap region 3199 is spaced apart from the narisopening 3102 in order to avoid potential interference (e.g., thatcreates noise) of pressurized air into the patient's nares. The overlapregion 4000 substantially on the first curvature 10000, and may provideadditional support for maintaining the appropriate magnitude for thefirst curvature 10000.

As shown in FIG. 59 , some examples of the patient interface may includea dual walled support structure 3120 coupled to the textile membrane3130. A single wall of silicone material may be molded to the textilemembrane 3130, in order to connect the seal-forming structure 3100 tothe plenum chamber 3200. As described above, the outer surface 3195substantially matches the outer surface 3196 of the textile membrane3130, and the inner surface 3197 includes varying thicknesses along itslength. However, the overlap region 3199 may extend a different lengthalong the inner surface 3194 of the textile membrane 3130. Specifically,the overlap region 3199 may contact a length of the textile membrane3130 that is less than in the single wall support structure 3120,described above. Instead, a portion of the silicone wall 3126 maycontinue to extend along a length of the textile membrane 3130, butspaced apart from the inner surface 3194. This second wall 3126 of thesupport structure 3120 may extend in a cantilevered manner from theremainder of the lateral support region (i.e., from end 3124). Thesupport structure 3120, with the inclusion of the second wall 3126, mayextend along a similar total overlapped length as the support structure3120 in the single wall example. The second wall 3126 may particular bedisposed proximate to an apex of the first curvature 10000, in order toprovide additional support. The second wall 3126 is stiffer than thetextile membrane 3130, and may assist in maintaining the shape of firstcurvature 10000 when the textile membrane 3130 contacts the patient'sface. If additional force is applied, the textile membrane 3130 and thesecond wall 3126 may deform together.

After assembling the textile membrane 3130 to the support structure3120, the resulting cushion assembly 3105 may be used in a patientinterface 3000. Specifically, the patient's face (e.g., the patient'snose) may be positioned within the space 3180 so that the naris openings3102 are positioned proximate to the respective nares.

When positioning the cushion assembly 3105, the patient may align thebridge portion 3104 with their nose. Specifically, the bridge portion3104 may be directed in the anterior/posterior direction as the cushionassembly 3105 is donned (e.g., the textile membrane 3130 may besubstantially facing the superior direction). The patient moves thebridge portion 3104 into contact with their nose, where the tautmaterial of the bridge portion 3104 presses against the patient's nose(e.g., in the subnasale region and may contact the columella). Thebridge portion 3104 limits the patient's nose from moving into thecavity 3101, but as the patient's nose presses against the tautmaterial, tension may be applied to the surrounding regions on thetextile membrane 3130. In other examples, the patient may move theirface toward a separate area of the textile membrane 3130 that is undertension (e.g., if the entire area of the textile membrane is undertension like in FIGS. 26-33 ).

While the patient contacts the bridge portion 3104, the patient may alsocontact the lateral side 3250 and/or corner regions 3252 of the textilemembrane. The lateral side 3250 and the corner region are disposed on aregion of the third curvature 30000 proximate to an apex of the firstcurvature 10000. In other words, the lateral side 3250 and corner region3252 are disposed on a surface having a saddle region, and face toward acenter of the cushion assembly 3105. A positive curvature may be betweenthe opposing lateral sides 3250. The lateral side 3250 and cornerregions 3252 are also positioned proximate to where the textile membranetransitions to a negative dome curvature (i.e., formed by the firstcurvature 10000), and may be understood to be at a posterior portion ofthe cushion assembly 3105. This transition region may be understood tobe a domed region of the sealing portion 3130. The lateral side 3250and/or the corner regions 3252 contact the outer surface of thepatient's nose (e.g., proximate to the patient's nasal ala), and mayterminate proximate to the alar crest points on either side of thepatient's nose. In this orientation, the naris openings 3102 are alignedwith the patient's nares, and may effectively deliver pressurized air tothe patient's airways. The lateral side 3250 and/or corner regions 3252are generally loose, which allows these regions of the textile membrane3130 to better form to the various contours of the patient's face. Forexample, the lateral side 3250 and/or corner regions 3252 may be able toadjust in shape in order to better conform to the region surrounding thepatient's nares in order to develop a tight seal. As the patient's noseengages the bridge portion 3104, the lateral side 3250 and/or cornerregions 3252 may experience tension, in order to maintain theappropriate shape from the patient.

As shown in FIG. 60 , the textile membrane 3130 may include an arch60000 adjacent each of the naris openings 3102. The arches 60000 arealso disposed proximate to the lateral side 3250 and/or corner regions3252. The arches 60000 have a saddle region in the same direction as thefirst curvature 10000 (and may also be about the first axis 11000). Thearches 60000 extend into the space 3180 so that a distance between thearches 60000 may be the narrowest distance between opposing lateralsides 3250 and/or corner regions 3252.

When the patient dons the cushion assembly 3105, the naris openings 3102may have a generally vertical alignment (as described above), and aninner surface of each nostril contacts the respective arch 60000. Inother words, the each arch 60000 is configured to contact an innersurface of the each respective nasal ala. Since the patient's nose isalso contacting the bridge portion 3104 of the textile membrane 3130,each naris opening 3102 fully surrounds each respective naris.

As shown in FIG. 61 , once each of the arches 60000 contacts the innersurface of the respective naris, the arch 60000 flips to a concaveorientation (i.e., a positive dome curvature relative to the innersurface of the respective naris). This is similar to what occurred withthe bridge portion 3104, although a curvature of the arches 60000 may bedirected in a different direction. For example, each arch 60000 may movealong the first axis 11000 toward the respective plenum chamberconnector 3204. In this orientation, each naris opening may have asubstantially tear-drop shape.

When the arch 60000 flips (i.e., from a negative dome curvature to apositive dome curvature), the arch 60000 may wrap around an alar rim ofthe respective naris. In other words, each arch 60000 wraps around theouter periphery of the respective naris. The compliant nature of thetextile membrane 3130 allows the arches 60000 to adjust to the shape ofthe patient's alar rim in order to form a seal sufficient to maintainthe therapeutic pressure within the plenum chamber 3200.

Once the cushion assembly 3105 is properly positioned, the patient maysupply pressurized air. The compliant nature of the textile membrane3130, and the fact that the outer portions are initial loose (e.g., asopposed to taut like the bridge portion), allows the seal-formingstructure 3100 to form a dynamic seal as pressurized air fills thecavity 3101. The dynamic seal allows the cushion assembly to shiftslightly on the patient's nose, while still maintaining a pressurizedcavity 3101, and delivering pressurized air to the patient's airways.For example, the arches 60000 may be able to slightly move against thealar rims without losing their seal.

Additionally, the third, fourth, and/or fifth curvatures 30000, 40000,50000 may provide additional assistance in maintaining the position ofthe seal-forming structure 3100, and enhancing comfort for the patient.For example, the third curvature 30000 may have a saddle region relativeto the patient, and may contact the subnasale region of the patientalong the columella (e.g., via a positive curvature). The thirdcurvature 30000 may not extend to the patient's pronasale, leaving itexposed. The third curvature 30000 may be disposed in the pronasaleregion 3270 of the textile membrane 3130. The fourth curvature 40000 mayhave a saddle region relative to the patient, and may contact thepatient's lip superior (e.g., via a positive curvature). Thus, thefourth curvature 40000 extends in the lateral (left/right) directionwhile worn by the patient, and may also extend substantially along themouth width. The fifth curvature 50000 may have a negative domecurvature relative to the patient's lip superior. In other words, thefifth curvature 50000 curves away from, and does not cradle, thepatient's lip superior. The fourth and fifth curvatures 40000, 50000 maycontact substantially the same region of the patient's face, and one orboth may be included on a given textile membrane 3130. The fourth and/orfifth curvatures 40000, 50000 may be disposed in the medial subnasaleregion 3260 of the textile membrane 3130. The fifth curvature 50000 maycreate a “pillow” and/or “airbag” effect on the patient. In other words,the negative dome curvature of the fifth curvature, relative to thepatient's lip superior in use, may provide additional cushioning and/orcomfort to the patient as a result of the pressurized air inflating thetextile membrane 3130.

While the above description was specifically directed toward a nasalcradle, it is equally applicable to the patient interfaces 9000, 21000,23000, 25000 described above. Additional description specific to thefull face cushion is described below.

5.3.4.1.1.1 Full Face Cushion

In addition to the steps described above, manufacturing and assemblingthe full face cushion differs from the nasal cushion because of theadditional area that the full face cushion is required to seal around(i.e., both the patient's nares and mouth). Accordingly, additionalsurface area of textile membrane 10135 is required, and additionalsurface area of the support structure 6120 (e.g., silicone material) isrequired, since the overall size of the full face cushion is larger thanthe nasal cushion.

The patient interfaces, illustrated in FIGS. 22 to 39 , are assembled byplacing two pieces of textile membrane 10135 into a molding tool, andmolding a flexible material (e.g., silicone) onto the textile membranes10135 in order to form the patient interface 6000, 9000, 21000, 23000,25000. In these examples, the two textile membranes 10135 are differentshapes, in order to seal with a specific region on the patient's face(although a single textile membrane 10135 could be used). As describedabove, the first textile membrane 10135 (i.e., used to form the firstsealing portion 6131) has a rounded shape, and the second textilemembrane 10135 includes a U-shape or a C-shape (see e.g., FIG. 33 ), ora ring or annular shape (see e.g., FIG. 33-1 ). The textile membranes10135 are substantially flat (e.g., having a two-dimensional shape)prior to being placed into the mold. Once they are positioned in themold, the two textile membranes 10135 are spaced slightly apart from oneanother (e.g., via a gap 21190). In some examples, the mold maintainsthe textile membrane 10135 in a partially flat position as the flexiblematerial (e.g., silicone) is introduced into the mold (e.g., the patientinterface 6000). In some examples, the mold introduces curvatures to thetextile membranes 10135 and holds the textile membranes 10135 in theircurved shape as flexible material (e.g., silicone) is introduced intothe mold (e.g., the patient interface 9000, 21000, 23000, 25000). Thecurvatures introduced to the textile membranes 10135 by the mold maycause the bridge portion (e.g., 9106) to fold on itself. As the flexiblematerial is introduced into the mold and hardens, it secures the twoflexible textile membranes 10135 together. After the molding process iscomplete, the bridge portion 9106 can be crimped in order to removeslack from the textile membrane 10135. Alternatively, the bridge portion9106 can be crimped prior to positioning the textile membranes 10135 inthe mold. This may impart a pre-deformation onto the textile membranes10135 (e.g., the textile membranes 10135 deform prior to beingpositioned within the mold and having additional curvatures imparted onthe remainder of the textile membranes 10135). The bridge portion 6106may not need to be crimped since the textile membrane 10135 was held intaut position by the mold, and may be generally flat along the lateraldirection. The bridge portion 6106 may be under tension without a crimp,and may apply substantially the same benefits as the bridge portionswith a crimp. As noted previously, it may be easier to manufacture thetextile membrane 10135 into the first sealing structure 6131 as opposedto the first sealing structure on another patient interface (e.g., 9000)since the first sealing structure 6131 may not include complexcurvatures.

By using two separate pieces of textile membrane 10135 to form thepatient interface (e.g., 9000, 21000, etc.), overlap of the textilematerial 10135 can be avoided. Particularly, overlap may be an issuewhen attempting to impart complex curvatures onto a large piece oftextile membrane 10135, because longer curvatures may be possible, whichmay lead to more opportunities for the textile membrane 10135 to fold onitself. Since the patient interface 6000 does not include complexcurvatures, overlap of the textile material 10135 may be less likely.However, using two separate pieces of textile material 10135 may allowthe patient interface 6000 to include a substantially planar surface ofthe first sealing structure 6131 oriented in a first direction, and asubstantially planar surface of the second sealing structure 6132 in asecond direction. In other words, the separate pieces of textilemembranes 10135 may be disposed in different orientations in order tobetter conform to a patient's face as a result of the patient interface6000 being constructed from separate textile membranes 10135.

One way to solve the issue of overlap was to stack multiple pieces ofthe textile membrane 10135 on top of one another to produce complexcurvatures (e.g., by creating an overlap of a few millimeters with twoor more textile membranes 10135), while reducing the stress experiencedin each textile membrane 10135 (e.g., as compared to a single textilemembrane 10135). However, leaks could occur in the overlapped region,which could degrade the quality of the seal in the eventual patientinterface 9000, 21000, etc.

If two separate pieces of the textile membrane 10135 are used but notoverlapped, the likelihood that a single piece of textile membrane 10135will fold on itself is reduced because the length of each individualcurve is reduced. Additionally, the likelihood of leaks occurring may bereduced from an example where the textile membranes 10135 overlap, sincethe overlapping interface of textile membranes 10135 has been removed.

Two spaced apart pieces of textile membrane 10135 are used, and theflexible material may be molded in the space between the two textilemembranes 10135. As illustrated, this space may be relatively small(e.g., in order to reduce contact between the patient's skin and thesupport structure 9120, 21120, etc.). As a result, this may make moldingthis section of the patient interface (e.g., 9000, 21000, etc.)difficult (e.g., because the textile membranes 10135 have to beaccurately positioned, the flexible material has to fill the spacewithout covering the textile layer 10133, etc.), but may increase thelikelihood that the resulting patient interface (e.g., 9000, 21000,etc.) will not include creases formed as a result of the complexcurvatures imparted on the textile membrane 10135. A similar principlemay be true for the patient interface 6000, even though there are nocomplex curvatures in the first sealing portion 6131.

In this example, there is a direct trade-off between ease ofmanufacturing, and full textile contact. For example, the patientinterface 9000 shown in FIG. 35 (or the patient interface 6000 in FIG.33 ) may be easier to manufacture than the patient interface 21000 shownin FIG. 33-1 (e.g., because the liquid material may not be molded intoas small of spaces). However, the patient's lip superior (e.g.,proximate to the philtrum) will contact a larger surface area of thesupport structure 9120 (i.e., not the textile layer 10133) in theexample shown in FIG. 35 , potentially having a lower comfort level forthe patient than the patient interface 21000 of FIG. 33-1 .

The example of the patient interface 23000 shown in FIG. 33-2 mayattempt to balance the issues observed in the patient interface 9000 ofFIG. 34 (or 6000 of FIG. 33 ) and the patient interface 21000 of 33-1.In other words, the patient interface 23000 of FIG. 33-2 may attempt toreduce the manufacturing complexity, without sacrificing patientcomfort. To do this, the second textile membrane 10133 may include aU-shape or C-shape (e.g., similar to the example shown in FIGS. 33 and35 ). The U-shaped textile membrane 10135 includes an outer edge 23180that forms a portion of the outer periphery of the lower sealing portion23130 b, and an inner edge 23182 that forms a portion of the oralportion hole 23104. The first textile membrane 10135, which forms theupper sealing portion 23130 a of FIG. 33-2 , may be larger than thefirst textile membrane 10135 that forms the upper sealing portion 21130a of FIG. 33-1 , so that a lower edge 23184 of the first textilemembrane 10135 may be aligned with the inner edge 23182 of the secondtextile membrane 10135. In other words, substantially all of theperimeter of the oral portion hole 23104 includes the textile membrane10135, as opposed to the support structure 23120. Since the textilemembranes 10135 are separate pieces, gaps 23190 filled with the flexiblematerial may still exist between the individual pieces (i.e., betweenthe upper and lower sealing portions 23130 a, 23130 b). These gaps 23190are generally in the longitudinal (e.g., left/right) direction, andextend at least between the outer and inner edges 23180, 23182. The gaps23190 may be small enough that the patient's comfort is not effected bytheir presence (e.g., the patient may not feel the support structure23120 between the sealing portions 23130 a, 23130 b, and may insteadfeel as though only textile material contacts the region around theirmouth). In some examples, the gap 23190 may be substantially small, sothat the patient may be unable to detect its presence.

In the mold, the textile membranes 10135 are arranged in the mannerdescribed above, and the flexible material is introduced into the moldto form the patient interface 23000. Since the lower edge 23184 of thefirst textile membrane 10135 extends to the inner edge 23182 of thesecond textile membrane, the flexible material is not introduced intothe mold in an area that will be between the naris opening 23103 and theoral portion hole 23104. In other words, the textile membrane 11035 isthe only material that is configured to contact the lip superior in thisregion (e.g., against the philtrum). Even though the flexible materialis able to bend and move, the combination of textile membrane 10135 withthe flexible material may reduce the resiliency of the patient interface23000. For example, during the molding process, the flexible materialmay solidify on an interior surface (i.e., within the cavity 23001) ofthe textile membrane 10135, which increases the thickness of thisregion. In use, the patient interface 23000 may have more difficultyflexing when the patient's lip superior contacts this region, which mayresult in an imperfect seal (i.e., allow for leaks). By removing theneed for the support region between the naris openings 23103 and theoral portion hole 23104, the flexible material does not need to flowinto this region, and the thickness of the textile membrane 10135 maynot substantially increase. Without the flexible material substantiallybacking the textile membranes 10135 (e.g., as in FIG. 33-1 ), thetextile membrane 10135 may be able to stretch as much as a patientinterface made entirely from silicone (e.g., 0.3 mm thick silicone), sothat the textile membrane 10135 can achieve substantially the same orsimilar quality of seal against the patient's face as with the entirelysilicone membrane.

In order to manufacture this patient interface 23000, the textilemembranes 10135 may be substantially flat (e.g., have a two-dimensionalshape) prior to being placed into the mold, and may receive complexcurvatures as a result of being placed into the mold. The liquidflexible material may be applied in order to form the three-dimensionalpatient interface 23000 (e.g., maintain the complex curvatures in thetextile membranes 10135 after being removed from the mold). As describedabove, any crimp may be applied either before or after the textilemembrane 10135 is placed into the mold.

As shown in FIG. 33-3 , the patient interface 25000 may be formed usinga single textile membrane 10135 when constructing the sealing portion25130. In other words, one sheet of textile membrane 10135 is used toseal around both the patient's nares and the patient's mouth. Thesealing portion 25000 includes an upper sealing portion 25130 a and alower sealing portion 25130 b. The outer perimeter of the sealingportion 25130 is substantially the same as the examples mentioned above.However, in this example, the support structure 25120 is not needed tobe formed between first and second textile membranes 10135 in order tospace them apart and connect them together. Thus, manufacturing may beeasier since textile membranes do not have to be properly spaced andfilled with the liquid mold material. Additionally, the entire area ofthe patient interface 25000 that contacts the patient proximate to themouth and/or nose is constructed from the textile layer 10133. This mayhelp to improve patient comfort, since the support structure 25120 willnot contact the patient proximate to their lip superior.

Using the crimp method described above, the likelihood of the singletextile membrane 10135 folding onto itself may be reduced or eliminated,even while using a larger piece of textile membrane 10135 (e.g., ascompared to the examples shown in FIGS. 33-1 and 33-2 ). Particularly,the crimp may reduce or eliminate overlap from occurring in the nasalregion, where more curvatures are applied.

Additionally, there may not be a significant drop off in the quality ofthe seal in the resulting patient interface (e.g., as compared to thepatient interfaces 21000, 23000 of FIGS. 33-1 and 33-2 ). The textilemembrane 10135 in FIG. 33-3 may include the textile layer 10133 backedwith the impermeable layer 10131, but the overall textile membrane 10135may be unbacked (e.g., may not be backed with the flexible material ofthe support structure 25120). The textile membrane 10135 may be able tostretch a similar amount as silicone alone (e.g., the impermeable layer10131 may not significantly reduce the stretchability of the textilemembrane 10135), and thus may be able to accommodate various contoursalong the patient's face (e.g., proximate to the patient's nasal ala),which may assist in forming the seal.

In order to reduce and/or eliminate leaks from occurring while thepatient interface 25000 is worn, the shape of the textile membrane 10135may be modified in order to better accommodate a wider range ofpatient's faces, and limit leaks from occurring (see e.g., FIGS. 33-4 to33-5 ). In one example, the modifications to the textile membrane 10135may include reducing the radius of curvature in the upper sealingportion 25130 a. Reducing the radius of curvature creates a deeperpocket or nasal radii to receive the patient's face. For example, theportion of the upper sealing portion 25130 a that receives the patient'snose may be narrower, so that when the patient's nose contacts thetextile layer 10133 of the sealing portion 25130, the textile membrane10135 is tighter against the patient's nose. This may be particularlybeneficial for patients with smaller and/or narrower noses, who foundthe sealing portion 25130 with a larger radius of curvature to fit tooloosely. Since the textile membrane 10135 are able to flex and deform,patient's with slightly larger noses may still use the patient interface25000, and experience the tight fit (e.g., in order to reduce leaks).

Additionally, reducing the radius of curvature of the upper sealingportion 25130 a may impart a similar shape on the join between thesealing portion 25130 and the support structure 25120. Since the uppersealing portion 25130 a and the support structure 25120 are connected,the support structure 25120 may be pulled in the direction of the deeppocket formed in the upper sealing portion 25130 a.

Reducing the radius of curvature of the upper sealing portion 25130 amay impart a similar shape on the lower sealing portion 25130 b, sincethe upper and lower sealing portions 25130 a, 25130 b are formed fromone piece of the same textile membrane 10135. This may specificallyreduce the curvature at the inferior end of the lower sealing portion25130 b (e.g., region configured to contact the patient's chin), andprovide similar benefits of the deeper pocket described above.

In some examples, the radius of curvature may be adjusted about thethird axis 13000. In other words, lateral sides 25250 and/or cornerregions 25252 of the patient interface 25000 may be closer together andthe patient may have to put their nose further into the cushion assembly25105 in order to contact the bridge portion 25106. Additionally, theradius of curvature about the fifth axis 15000 may be increased, so thatthe curvature is reduced. Increasing the radius of curvature about thefifth axis 15000 helps to maintain the deep curvature about the thirdaxis 13000 because the fifth curvature 50000 does not flatten out thethird curvature 30000 (e.g., as a result of the third curvature 30000and the fifth curvature 50000 being about non-parallel axes).

In some examples, the radius of curvature about the third axis may beless than approximately 40 mm. In some examples, the radius of curvatureabout the third axis may be less than approximately 30 mm. In someexamples, the radius of curvature about the third axis may be betweenapproximately 25 mm and approximately 15 mm. In some examples, theradius of curvature about the third axis may be approximately 20 mm.This radius of curvature may be in the textile membrane 10135 only. Byreducing the radius of curvature, the patient's nose is secured withinthe sealing portion with a tighter fit, and leaking may be reduced.Reducing the radius of curvature also assists the patient to moreaccurately position their nose against the patient interface 25000(e.g., to more accurately align their nares with the respective narisopenings 25103) because there is less room for the patient's nose tomove laterally (e.g., slide and/or shift) against the patient interface25000.

Leaks may also be prevented and/or reduced by reinforcing the sealingportion 25130 and/or the support structure 25120. As shown in FIG. 33-6, support ribs 25186 may be added within the cavity 25001 in order toincrease the localized stiffness of the patient interface, and improvethe quality of the seal against the patient's skin. In some examples, asupport rib 25186 may be included and/or enlarged in order to increasethe localized stiffness. In some examples, the support rib 25186 isenlarged by adding a secondary rib 25188. In some examples, the supportrib 25186 is enlarged by increasing its width. In some examples, thesupport rib 25186 is enlarged by increasing its length.

In one example, the support rib 25186 is molded to the patient interface25000 within the cavity 25001, and the secondary rib 25188 is molded toan end of the support rib 25186. One end of the support rib 25186 maycontact the impermeable layer 10131 of the sealing portion 25130, andthe secondary rib 25188 may be molded to the other end of the supportrib 25186. Together, the support rib 25186 and the secondary rib 25188may form an L-shape. The support rib 25816 may intersect the secondaryrib in approximately a perpendicular relationship. The secondary rib25188 may be parallel to at least a section of the sealing portion25130. In the illustrated example, the patient interface may include twosupport ribs 25186 (although any number is acceptable), which eachconnect to the sealing portion 25130. An inner end of each support rib25186 may extend between approximately 2 mm to approximately 8 mm froman inner edge of the sealing portion 25130 (e.g., a free end proximatean opening to the cavity 25001). Each secondary rib 25188 may not extendfurther so as to not block airflow through the naris openings 25103. Thesingle secondary rib 25188 may extend between the two support ribs25186. The ends of the secondary rib 25188 may connect to theimpermeable layer 10131 of the sealing portion 25130 so that thesecondary rib 25186 follows an arcuate pattern. In other examples, thesecondary rib 25188 may not extend beyond the furthest support ribs25186. In other words, the distance between the support ribs 25186 maybe approximately the length of the secondary rib 25188.

Including the secondary rib 25188 may improve the sealing of the patientinterface 25000 when worn by the patient. Specifically, the stiffness ofthe sealing portion 25130 may increase. For example, the portion of thesealing portion 25130 configured to contact the lip superior mayincrease in stiffness as a result of the support ribs 25186 and/or thesecondary rib 25188. The distance between the support ribs 25186, aswell as the number of support ribs 25186, may affect the total increasein stiffness. In other words, increasing the number of support ribs25186 and/or decreasing the distance between adjacent support ribs 25186will increase the stiffness of the sealing portion 25130. The secondaryrib 25188 may act as a backstop, and help limit the compression of thesupport ribs 25186 (e.g., because of contact with the patient's face).Increasing the stiffness may help to maintain the shape of the differentcurvatures, and allow for an ideal fit for the patient. For example, theribs 25186, 25188 assist in maintaining the various radii of curvatureof the sealing portion 25130, and limit creasing or folding fromoccurring, in order to limiting leaking from occurring.

In one example (see e.g., FIG. 33-7 ), the support ribs 25186 are moldedto the patient interface 25000 within the cavity 25001, with a lengththat is longer than the length shown in FIG. 33-6 . The support ribs25186 that have the larger width may be molded with or without thesecondary rib 25188. Increasing the width of the support ribs 25186decreases the likelihood that the support ribs 25186 will buckle whenthe patient dons the patient interface 25000. Thus, the stiffness of thesupport ribs 25186 will be greater, so there will be a decreasedlikelihood that the sealing portion 25130 will crease and/or fold.Providing the secondary rib 25188 in conjunction with the wider supportribs 25186 may increase the stiffness of the sealing portion 25130 morethan if only one of these modifications were included. However,increasing the thickness of the support ribs 25186 may specificallyincrease the stiffness in locations where they are attached to thesealing portion 25130 (i.e., a localized increase in stiffness), asopposed to the secondary rib 25188 increasing the stiffness around alarger area of the sealing portion 25130.

In one example, the support ribs 25186 are molded to the patientinterface 25000 within the cavity 25001, with a length that is longerthan the length shown in FIG. 33-7 . The longer support ribs 25186 maybe molded with or without the secondary rib 25188, and/or with orwithout the wider support ribs 25186. In some examples the length ofeach of the support ribs 25186 may increase by between approximately 0.1mm to approximately 8 mm. In some examples the length of each of thesupport ribs 25186 may increase by between approximately 0.5 mm toapproximately 5 mm. In some examples the length of each of the supportribs 25186 may increase by between approximately 1 mm to approximately 3mm. In some examples the length of each of the support ribs 25186 mayincrease by approximately 2.5 mm. Lengthening the support ribs 25186 mayprovide additional support for the portion of the sealing portion 25130along the third curvature 30000 that may contact the patient's lipsuperior.

Leaks may also be prevented and/or reduced by changing a shape of thepatient interface 25000 (see e.g., FIGS. 33-8 and 33-9 ). For example,the shape and/or contour of the lateral side 25250 and/or the cornerregions 25252 of the sealing portion 25130 may be adjusted in order tobetter conform to the patient's face (e.g., proximate the corner of noseor nasal ala region). The shape change to the sealing portion 25130 maybe caused by changing the shape of the support structure 25120. Sincethe support structure 25120 helps to determine where the sealing portion25130 sits, the shape of the support structure 25120 will change withthe shape of the sealing portion 25130.

In some examples, the first curvature 10000 may be adjusted in order toassist in providing an improved seal for the patient. Specifically, themagnitude of the first curvature 10000 may be more negative (i.e., thanin previously described examples) about the first axis 11000. Asdescribed above, the lateral side 25250 and/or the corner regions 25252are disposed on the sealing portion 25130 proximate a transition betweenthe positive curvature about the third axis 13000 (i.e., the thirdcurvature) and the first curvature 10000. By increasing the magnitude ofthe first curvature 10000, the positive dome shape may become morepronounced (e.g., the curvature is steeper). This may decrease the widthbetween the opposing lateral sides 25250, which may provide a tighterfit for the patient wearing the patient interface 25000, which in turncould limit the patient's nose from shifting against the sealing portion25130.

The shape of the support structure 25120 may also be adjusted in orderto limit and/or prevent leaks. Changing the shape of the supportstructure 25120 (e.g., molding a negative curvature with a largermagnitude) may also impart a shape change on the sealing portion 25130,since the support structure 25120 is molded to the sealing portion25130. This may be specifically shown in FIG. 33-9 , which shows thesealing portion 25130-1 after the shape change, and the sealing portion25130 before the shape change. Creating a larger positive dome shape inthe support structure 25120 creates a similar affect as described abovewith respect to the sealing portion 25130.

As shown in FIG. 33-10 , leaks may be prevented and/or limited byraising the top vector of the patient interface 25000. Similar to thepatient interface 9000 shown in FIG. 24 , the positioning andstabilizing structure 9300 may engage the patient interface 25000 atfour points of contact (i.e., two on either side) with the plenumchamber 25200 and/or the seal-forming structure 25100. For example, aclip 9301 and a conduit 9900 (see e.g., FIG. 24 ) connect on the leftside and on the right side of the cushion assembly 25105. When worn, thepatient may adjust a length of the upper strap 9302 and/or the conduits9900 may stretch (e.g., because of the elastomeric material, because ofconcertinas, etc.) in order to pull the cushion assembly 25105 againstthe patient's face. The tensile force from the positioning andstabilizing structure 9300 assists in forming a seal between the sealingportion 25130 (see e.g., FIG. 33-3 ) and the patient's face.

The sealing force from the tensile force may be improved by changing theposition that the clips 9301 and/or the conduits 9900 connect to thecushion assembly 25105. For example, changing the location of thevectors may allow the patient to achieve a tighter seal against theirface. This may be achieved by spacing the connection points of clip 9301and of the conduit 9900 further apart (i.e., on either lateral side). Inone example, the connection points for the conduits 9900 are raised fromthe position the example illustrated in FIG. 24 (e.g., and are closer tothe pronasale when worn). Raising where the conduits 9900 connect to thecushion assembly 25105 allows the force supplied by the conduits 9900 toact more directly on the nasal portion (e.g., proximate to the narisopenings 25103) of the cushion assembly 25105. Raising the conduitconnection point may also cause the forces applied by the conduits to bemore localized about the naris openings 25103 (e.g., so that a largercomponent of the force is applied at that location). Since the patient'snose includes a variety of contours, concentrating a greater portion ofthe force from the conduits 9900 may allow the sealing portion 25130 tomore accurately compliment the patient's facial geometry.

As shown in FIG. 33-10 , the upper vector may be raised from a firstheight H₁ to a second height H₂. The second height H₂ is closer to thenaris openings 25103 than the first height H₁. In some examples thedistance between the first height H₁ and the second height H₂ is atleast approximately 0.5 mm. In some examples the distance between thefirst height H₁ and the second height H₂ is between approximately 1 mmand approximately 10 mm. In some examples the distance between the firstheight H₁ and the second height H₂ is between approximately 2 mm andapproximately 8 mm In some examples the distance between the firstheight H₁ and the second height H₂ is between approximately 3 mm andapproximately 5 mm. In some examples the distance between the firstheight H₁ and the second height H₂ is approximately 4 mm.

As shown in FIG. 33-11 , leaks may be prevented and/or limited byapplying inserts 25194 to a surface of the cushion assembly 25105. Insome examples, the inserts 25194 may be constructed from a foammaterial, and may be disposed on an outer surface of the sealing portion25130 (e.g., in contact with the textile layer 10133). The inserts 25194may also be disposed on a surface of the support structure 25120 inaddition to and/or instead of being disposed on the sealing portion25130.

The inserts 25194 may be disposed at any location along the cushionassembly 25105. In the illustrated example, the inserts 25194 aredisposed at discrete locations throughout the cushion assembly 25105,and may specifically be disposed at locations susceptible to leaks. Forexample, this may be proximate to the lateral side 25150 and/or cornerregions 25252, which is configured to contact the nasal alar region ofthe patient's face. The inserts may be able to deform into the complexfacial geometry of the patient, in order to form a tighter seal, andreduce gaps through which air can escape. In some examples, the foam isnot exposed to the ambient when the cushion assembly 25105 is donned bythe patient. Thus, the insert 25194 provides additional material totighten the fit at some areas, but does not provide passages throughitself where air can leak.

In some examples, the inserts 25194 are permanently fixed to the cushionassembly 25105. For example, the inserts 25194 may be glue, or otherwisefixed, to a surface of the cushion assembly 25105 so that a patient isunable to remove the inserts 25194 without potentially damaging thecushion assembly 25105. In other examples, the inserts 25194 may beremovable so that the patient can position them in a variety oflocations, or remove the inserts 25194 entirely.

Any combination of the leak prevention and/or reduction examplesdescribed above and in FIGS. 33-1 to 33-11 may be used in a singlecushion assembly 25105. Including several of the above describedexamples may offer further improvements in preventing and/or limitingleaks from occurring. However, some patients may experiencesubstantially no leaks of pressurized air, and may not require a cushionassembly 25105 with any of these examples. For example, patients withlarger noses may have a more secure fit against an unmodified cushionassembly 6105, 9105, or their nose may be too tight against the modifiedcushion assembly 25105.

5.3.4.1.2 Textile Membrane Examples

Below are example properties and structural arrangements of the textilecomposite used as the material for the textile membrane.

5.3.4.1.2.1 Textile Composite Structure

Various combinations of textile materials and membrane/film layers maybe used. In an example, a three-layer arrangement including athermoplastic polyurethane (TPU) film disposed between two textilelayers (e.g., nylon, nylon and polyester mix, nylon and spandex mix,polyester and spandex mix, or nylon/polyester/spandex mix) is used. Theadditional textile layer is needed to protect the TPU film from breaking(e.g., during cleaning).

In another example, a two-layer arrangement including a textile (e.g.,nylon, nylon and polyester mix, nylon and spandex mix, polyester andspandex mix, or nylon/polyester/spandex mix) having a silicone layer(e.g., coated thereon) is used. This composite material may be lessexpensive than the three-layer arrangement discussed above, since onlyone layer of textile is needed.

In another example, a textile material (e.g., a microfiber orpolyurethane material) may be coated with a polyurethane film to form atwo-layer arrangement.

5.3.4.1.2.2 Textile Material

As described above, a number of textile materials maybe used to form thesealing portion, such as nylon, polyester, spandex, nylon and polyestermix, nylon and spandex mix, polyester and spandex mix,nylon/polyester/spandex mix, microfiber or polyurethane.

In an example, a nylon material is used. Nylon may provide comfortbenefits to the patient as it is softer than polyester. Nylon is alsomore durable than polyester and therefore provides enhancements in lifespan and durability. Further, as compared to polyester, nylon has ahigher melt temperature and therefore is able to withstand highertemperature manufacturing conditions.

In another example, a nylon and polyester mix material is used. Thismaterial may be more desirable as it absorbs moisture less readily dueto the addition of polyester and therefore reduces irritation to thepatient. The nylon and polyester mix is also less expensive than nylon.

5.3.4.1.2.3 Textile Composite Total Thickness

Thicker textile membrane thicknesses (e.g., 0.5 mm) may be sturdier andprovide a less flimsy impress. These textile membranes may be easier tohandle during manufacturing as they are less likely to flop around.

A middle range thickness (e.g., 0.35 mm to 0.45 mm) may provide aflexible, lightweight structure that is relatively easy to handle duringmanufacturing and may provide more comfort to the patient than a thickertextile membranes.

A thinner textile membrane may provide a very lightweight structure thatprovides a soft comfortable touch to the patient, but may provide lessdurability than thicker textile membranes.

5.3.4.1.2.4 Knit Structure

The textile material of the textile membrane may have a weft knitstructure or, alternatively, a warp knit structure, for example. Atextile material with a weft and/or warp knit structure may beconsidered a stretch textile. A weft knit textile may be more desirableas this may provide the material with higher elasticity as compared to awarp knit textiles. This may be advantageous as it may provide morecomfort to the patient by stretching as the patient's face engages thetextile membrane thereby reducing the force applied to the patient'sface by the textile membrane.

In an example, the weft direction (direction of the course 80) mayextend in the nose width direction of the textile membrane, since theweft direction may have greater elasticity or stretch. Alternatively,the weft direction may extend in the nose length direction(superior-inferior direction).

Additionally, weft knitting is more suitable for producing relativelythin materials, such as discloses herein. Also, weft knitting isgenerally less cost prohibitive than warp knitting.

However, in some examples, warp knitting may be desirable as it providesless shrinkage than weft knit materials.

In some examples, the textile membrane may include any knit structurethat allows the textile membrane to stretch.

In other examples, the textile membrane may include a differentstructure (e.g., woven), but may still be considered a stretch textile.

5.3.4.1.2.5 Knitting Machine

A weft knit textile material may have a single jersey knit structurewhich provides a technical face and a technical back that have differentappearances. A single jersey knit may be formed by one set of needlesand may provide knit stitches on the technical face (front) and purlstitches on the technical back. In an example, the technical face mayform the outer surface of the textile membrane and the air impermeablemembrane may be attached to the technical back. Alternatively, thetechnical face could be oriented towards an inner surface of the textilemembrane and have the membrane attached thereto.

In an example where the textile membrane includes an air impermeablemembrane sandwiched between two textile layers, the technical face ofeach textile material may form the exposed surfaces of the textilemembrane.

5.3.4.1.2.6 Textile Weight

The textile material may have a weight in the range of 95 grams persquare meter (gsm) to 130 gsm (e.g., 105 gsm to 120 gsm, or 110 gsm to115 gsm, or 105 gsm, or 110 gsm, or 120 gsm). A heavier weight textile(e.g., 120 gsm) may provide a desirable comfortable textile feel evenafter being coated with a laminate layer due to theweightiness/thickness of the textile. A lighter weight textile (e.g.,105 gsm) may be desirable as it provides a lighter product.

5.3.4.1.2.7 Machine Gauge

The machine gauge (i.e., the number of stitches per inch) of the textilematerial may vary. For example, the machine gauge may be in the range of35GG to (e.g., 44GG to 60GG, or 50GG to 55GG, or 55GG to 60GG, or 44GG,or or 55GG, or 60GG).

Using relatively larger gauge materials (e.g., 44GG) may be desirable asthis provides greater options for melange materials. However, a finergauge materials (e.g., 60GG) may be desirable as this softer materialswhich may enhance patient comfort.

5.3.4.1.2.8 Aesthetic

The textile material may have a solid color aesthetic or a melangeaesthetic. A melange material may be considered a material that has beenmade with more than one color of fabric/textile/yarn, either by usingdifferent color fabrics/textiles/yarns or made with differentfabrics/textiles/yarns which are then individually dyed. A melangematerial may be desirable as it may have a greater ability to hide dirtor grime thereby more easily improving the sense of cleanliness of theproduct. A melange material may also provide benefits duringmanufacturing as it is easier to visually align the textile knitstructure correctly during cutting and/or overmolding.

However, a solid color material may be desirable as it provides greateroptions for finer gauge materials (e.g., 55GG+) which are softer andtherefore more comfortable to the patient.

5.4 RPT DEVICE

An RPT device 4000 in accordance with one aspect of the presenttechnology comprises mechanical, pneumatic, and/or electrical componentsand is configured to execute one or more algorithms 4300, such as any ofthe methods, in whole or in part, described herein. The RPT device 4000may be configured to generate a flow of air for delivery to a patient'sairways, such as to treat one or more of the respiratory conditionsdescribed elsewhere in the present document.

In one form, the RPT device 4000 is constructed and arranged to becapable of delivering a flow of air in a range of −20 L/min to +150L/min while maintaining a positive pressure of at least 6 cmH₂O, or atleast 10cmH₂O, or at least 20 cmH₂O.

The RPT device may have an external housing 4010, formed in two parts,an upper portion 4012 and a lower portion 4014. Furthermore, theexternal housing 4010 may include one or more panel(s) 4015. The RPTdevice 4000 comprises a chassis 4016 that supports one or more internalcomponents of the RPT device 4000. The RPT device 4000 may include ahandle 4018.

The pneumatic path of the RPT device 4000 may comprise one or more airpath items, e.g., an inlet air filter 4112, an inlet muffler 4122, apressure generator 4140 capable of supplying air at positive pressure(e.g., a blower 4142), an outlet muffler 4124 and one or moretransducers 4270, such as pressure sensors and flow rate sensors.

One or more of the air path items may be located within a removableunitary structure which will be referred to as a pneumatic block 4020.The pneumatic block 4020 may be located within the external housing4010. In one form a pneumatic block 4020 is supported by, or formed aspart of the chassis 4016.

The RPT device 4000 may have an electrical power supply 4210, one ormore input devices 4220, a pressure generator 4140, and transducers4270. Electrical components 4200 may be mounted on a single PrintedCircuit Board Assembly (PCBA) 4202. In an alternative form, the RPTdevice 4000 may include more than one PCBA 4202.

5.4.1 RPT Device Mechanical & Pneumatic Components

An RPT device may comprise one or more of the following components in anintegral unit. In an alternative form, one or more of the followingcomponents may be located as respective separate units.

5.4.1.1 Air Filter(s)

An RPT device in accordance with one form of the present technology mayinclude an air filter 4110, or a plurality of air filters 4110.

In one form, an inlet air filter 4112 is located at the beginning of thepneumatic path upstream of a pressure generator 4140.

In one form, an outlet air filter 4114, for example an antibacterialfilter, is located between an outlet of the pneumatic block 4020 and apatient interface 3000.

5.4.1.2 Muffler(s)

An RPT device in accordance with one form of the present technology mayinclude a muffler 4120, or a plurality of mufflers 4120.

In one form of the present technology, an inlet muffler 4122 is locatedin the pneumatic path upstream of a pressure generator 4140.

In one form of the present technology, an outlet muffler 4124 is locatedin the pneumatic path between the pressure generator 4140 and a patientinterface 3000.

5.4.1.3 Pressure Generator

In one form of the present technology, a pressure generator 4140 forproducing a flow, or a supply, of air at positive pressure is acontrollable blower 4142. For example the blower 4142 may include abrushless DC motor 4144 with one or more impellers. The impellers may belocated in a volute. The blower may be capable of delivering a supply ofair, for example at a rate of up to about 120 litres/minute, at apositive pressure in a range from about 4 cmH₂O to about 20 cmH₂O, or inother forms up to about 30 cmH₂O when delivering respiratory pressuretherapy. The blower may be as described in any one of the followingpatents or patent applications the contents of which are incorporatedherein by reference in their entirety: U.S. Pat. Nos. 7,866,944;8,638,014; 8,636,479; and PCT Patent Application Publication No. WO2013/020167.

The pressure generator 4140 may be under the control of the therapydevice controller 4240.

In other forms, a pressure generator 4140 may be a piston-driven pump, apressure regulator connected to a high pressure source (e.g. compressedair reservoir), or a bellows.

5.4.1.4 Transducer(s)

Transducers may be internal of the RPT device, or external of the RPTdevice. External transducers may be located for example on or form partof the air circuit, e.g., the patient interface. External transducersmay be in the form of non-contact sensors such as a Doppler radarmovement sensor that transmit or transfer data to the RPT device.

In one form of the present technology, one or more transducers 4270 arelocated upstream and/or downstream of the pressure generator 4140. Theone or more transducers 4270 may be constructed and arranged to generatesignals representing properties of the flow of air such as a flow rate,a pressure or a temperature at that point in the pneumatic path.

In one form of the present technology, one or more transducers 4270 maybe located proximate to the patient interface 3000.

In one form, a signal from a transducer 4270 may be filtered, such as bylow-pass, high-pass or band-pass filtering.

5.4.1.5 Anti-Spill Back Valve

In one form of the present technology, an anti-spill back valve 4160 islocated between the humidifier 5000 and the pneumatic block 4020. Theanti-spill back valve is constructed and arranged to reduce the riskthat water will flow upstream from the humidifier 5000, for example tothe motor 4144.

5.4.2 RPT Device Electrical Components 5.4.2.1 Power Supply

A power supply 4210 may be located internal or external of the externalhousing 4010 of the RPT device 4000.

In one form of the present technology, power supply 4210 provideselectrical power to the RPT device 4000 only. In another form of thepresent technology, power supply 4210 provides electrical power to bothRPT device 4000 and humidifier 5000.

5.4.2.2 Input Devices

In one form of the present technology, an RPT device 4000 includes oneor more input devices 4220 in the form of buttons, switches or dials toallow a person to interact with the device. The buttons, switches ordials may be physical devices, or software devices accessible via atouch screen. The buttons, switches or dials may, in one form, bephysically connected to the external housing 4010, or may, in anotherform, be in wireless communication with a receiver that is in electricalconnection to a central controller.

In one form, the input device 4220 may be constructed and arranged toallow a person to select a value and/or a menu option.

5.5 AIR CIRCUIT

An air circuit 4170 in accordance with an aspect of the presenttechnology is a conduit or a tube constructed and arranged to allow, inuse, a flow of air to travel between two components such as RPT device4000 and the patient interface 3000.

In particular, the air circuit 4170 may be in fluid connection with theoutlet of the pneumatic block 4020 and the patient interface. The aircircuit may be referred to as an air delivery tube (see e.g., 6348 inFIG. 7 ). In some cases there may be separate limbs of the circuit forinhalation and exhalation. In other cases a single limb is used.

In some forms, the air circuit 4170 may comprise one or more heatingelements configured to heat air in the air circuit, for example tomaintain or raise the temperature of the air. The heating element may bein a form of a heated wire circuit, and may comprise one or moretransducers, such as temperature sensors. In one form, the heated wirecircuit may be helically wound around the axis of the air circuit 4170.The heating element may be in communication with a controller such as acentral controller. One example of an air circuit 4170 comprising aheated wire circuit is described in U.S. Pat. No. 8,733,349, which isincorporated herewithin in its entirety by reference.

5.5.1 Supplementary Gas Delivery

In one form of the present technology, supplementary gas, e.g. oxygen,4180 is delivered to one or more points in the pneumatic path, such asupstream of the pneumatic block 4020, to the air circuit 4170, and/or tothe patient interface 3000.

5.6 HUMIDIFIER

In one form of the present technology there is provided a humidifier5000 (e.g. as shown in FIG. 5A) to change the absolute humidity of airor gas for delivery to a patient relative to ambient air. Typically, thehumidifier 5000 is used to increase the absolute humidity and increasethe temperature of the flow of air (relative to ambient air) beforedelivery to the patient's airways.

5.7 BREATHING WAVEFORMS

FIG. 5 shows a model typical breath waveform of a person while sleeping.The horizontal axis is time, and the vertical axis is respiratory flowrate. While the parameter values may vary, a typical breath may have thefollowing approximate values: tidal volume Vt 0.5 L, inhalation time Ti1.6 s, peak inspiratory flow rate Qpeak L/s, exhalation time Te 2.4 s,peak expiratory flow rate Qpeak −0.5 L/s. The total duration of thebreath, Ttot, is about 4 s. The person typically breathes at a rate ofabout 15 breaths per minute (BPM), with Ventilation Vent about 7.5L/min. A typical duty cycle, the ratio of Ti to Ttot, is about 40%.

5.8 PORTABLE OXYGEN CONCENTRATOR (POC)

Portable oxygen concentrators may take advantage of pressure swingadsorption (PSA). Pressure swing adsorption may involve using one ormore compressors to increase gas pressure inside a canister thatcontains particles of a gas separation adsorbent arranged in a “sievebed”. As the pressure increases, certain molecules in the gas may becomeadsorbed onto the gas separation adsorbent. Removal of a portion of thegas in the canister under the pressurized conditions allows separationof the non-adsorbed molecules from the adsorbed molecules. The gasseparation adsorbent may be regenerated by reducing the pressure, whichreverses the adsorption of molecules from the adsorbent. Further detailsregarding oxygen concentrators may be found, for example, in U.S.Published Patent Application No. 2009-0065007, published Mar. 12, 2009,and entitled “Oxygen Concentrator Apparatus and Method”, which isincorporated herein by reference.

Ambient air usually includes approximately 78% nitrogen and 21% oxygenwith the balance comprised of argon, carbon dioxide, water vapor andother trace gases. If a gas mixture such as air, for example, is passedunder pressure through a canister containing a gas separation adsorbentbed that attracts nitrogen more strongly than it does oxygen, part orall of the nitrogen will stay in the bed, and the gas coming out of thecanister will be enriched in oxygen. When the bed reaches the end of itscapacity to adsorb nitrogen, it can be regenerated by reducing thepressure, thereby releasing the adsorbed nitrogen. It is then ready foranother cycle of producing oxygen enriched air. By alternating canistersin a two-canister system, one canister can be separating oxygen whilethe other canister is being purged (resulting in a continuous separationof the oxygen from the nitrogen). In this manner, oxygen enriched aircan be accumulated, such as in a storage container or otherpressurizable vessel or conduit coupled to the canisters, for a varietyof uses including providing supplemental oxygen to patients.

5.9 GLOSSARY

For the purposes of the present technology disclosure, in certain formsof the present technology, one or more of the following definitions mayapply. In other forms of the present technology, alternative definitionsmay apply.

5.9.1 General

Air: In certain forms of the present technology, air may be taken tomean atmospheric air, and in other forms of the present technology airmay be taken to mean some other combination of breathable gases, e.g.oxygen enriched air.

Ambient: In certain forms of the present technology, the term ambientwill be taken to mean (i) external of the treatment system or patient,and (ii) immediately surrounding the treatment system or patient.

For example, ambient humidity with respect to a humidifier may be thehumidity of air immediately surrounding the humidifier, e.g. thehumidity in the room where a patient is sleeping. Such ambient humiditymay be different to the humidity outside the room where a patient issleeping.

In another example, ambient pressure may be the pressure immediatelysurrounding or external to the body.

In certain forms, ambient (e.g., acoustic) noise may be considered to bethe background noise level in the room where a patient is located, otherthan for example, noise generated by an RPT device or emanating from amask or patient interface. Ambient noise may be generated by sourcesoutside the room.

Automatic Positive Airway Pressure (APAP) therapy: CPAP therapy in whichthe treatment pressure is automatically adjustable, e.g. from breath tobreath, between minimum and maximum limits, depending on the presence orabsence of indications of SDB events.

Continuous Positive Airway Pressure (CPAP) therapy: Respiratory pressuretherapy in which the treatment pressure is approximately constantthrough a respiratory cycle of a patient. In some forms, the pressure atthe entrance to the airways will be slightly higher during exhalation,and slightly lower during inhalation. In some forms, the pressure willvary between different respiratory cycles of the patient, for example,being increased in response to detection of indications of partial upperairway obstruction, and decreased in the absence of indications ofpartial upper airway obstruction.

Flow rate: The volume (or mass) of air delivered per unit time. Flowrate may refer to an instantaneous quantity. In some cases, a referenceto flow rate will be a reference to a scalar quantity, namely a quantityhaving magnitude only. In other cases, a reference to flow rate will bea reference to a vector quantity, namely a quantity having bothmagnitude and direction. Flow rate may be given the symbol Q. ‘Flowrate’ is sometimes shortened to simply ‘flow’ or ‘airflow’.

In the example of patient respiration, a flow rate may be nominallypositive for the inspiratory portion of a breathing cycle of a patient,and hence negative for the expiratory portion of the breathing cycle ofa patient. Device flow rate, Qd, is the flow rate of air leaving the RPTdevice. Total flow rate, Qt, is the flow rate of air and anysupplementary gas reaching the patient interface via the air circuit.Vent flow rate, Qv, is the flow rate of air leaving a vent to allowwashout of exhaled gases. Leak flow rate, Ql, is the flow rate of leakfrom a patient interface system or elsewhere. Respiratory flow rate, Qr,is the flow rate of air that is received into the patient's respiratorysystem.

Flow therapy: Respiratory therapy comprising the delivery of a flow ofair to an entrance to the airways at a controlled flow rate referred toas the treatment flow rate that is typically positive throughout thepatient's breathing cycle.

Humidifier: The word humidifier will be taken to mean a humidifyingapparatus constructed and arranged, or configured with a physicalstructure to be capable of providing a therapeutically beneficial amountof water (H₂O) vapour to a flow of air to ameliorate a medicalrespiratory condition of a patient.

Leak: The word leak will be taken to be an unintended flow of air. Inone example, leak may occur as the result of an incomplete seal betweena mask and a patient's face. In another example leak may occur in aswivel elbow to the ambient.

Noise, conducted (acoustic): Conducted noise in the present documentrefers to noise which is carried to the patient by the pneumatic path,such as the air circuit and the patient interface as well as the airtherein. In one form, conducted noise may be quantified by measuringsound pressure levels at the end of an air circuit.

Noise, radiated (acoustic): Radiated noise in the present documentrefers to noise which is carried to the patient by the ambient air. Inone form, radiated noise may be quantified by measuring soundpower/pressure levels of the object in question according to ISO 3744.

Noise, vent (acoustic): Vent noise in the present document refers tonoise which is generated by the flow of air through any vents such asvent holes of the patient interface.

Oxygen enriched air: Air with a concentration of oxygen greater thanthat of atmospheric air (21%), for example at least about 50% oxygen, atleast about 60% oxygen, at least about 70% oxygen, at least about 80%oxygen, at least about 90% oxygen, at least about 95% oxygen, at leastabout 98% oxygen, or at least about 99% oxygen. “Oxygen enriched air” issometimes shortened to “oxygen”.

Medical Oxygen: Medical oxygen is defined as oxygen enriched air with anoxygen concentration of 80% or greater.

Patient: A person, whether or not they are suffering from a respiratorycondition.

Pressure: Force per unit area. Pressure may be expressed in a range ofunits, including cmH₂O, g-f/cm 2 and hectopascal. 1 cmH₂O is equal to 1g-f/cm 2 and is approximately 0.98 hectopascal (1 hectopascal=100 Pa=100N/m 2=1 millibar 0.001 atm). In this specification, unless otherwisestated, pressure is given in units of cmH₂O.

The pressure in the patient interface is given the symbol Pm, while thetreatment pressure, which represents a target value to be achieved bythe interface pressure Pm at the current instant of time, is given thesymbol Pt.

Respiratory Pressure Therapy: The application of a supply of air to anentrance to the airways at a treatment pressure that is typicallypositive with respect to atmosphere.

Ventilator: A mechanical device that provides pressure support to apatient to perform some or all of the work of breathing.

5.9.1.1 Materials

Fiber: A filament (mono or poly), a strand, a yarn, a thread or twinethat is significantly longer than it is wide. A fiber may includeanimal-based material such as wool or silk, plant-based material such aslinen and cotton, and synthetic material such as polyester and rayon. Afiber may specifically refer to a material that can be interwoven and/orinterlaced (e.g., in a network) with other fibers of the same ordifferent material.

Polycarbonate: a thermoplastic polymer of Bisphenol-A Carbonate.

Silicone or Silicone Elastomer: A synthetic rubber. In thisspecification, a reference to silicone is a reference to liquid siliconerubber (LSR) or a compression moulded silicone rubber (CMSR). One formof commercially available LSR is SILASTIC (included in the range ofproducts sold under this trademark), manufactured by Dow Corning.Another manufacturer of LSR is Wacker. Unless otherwise specified to thecontrary, an exemplary form of LSR has a Shore A (or Type A) indentationhardness in the range of about 35 to about 45 as measured using ASTMD2240.

Textile: A material including at least one natural or artificial fiber.In this specification, a textile may refer to any material that isformed as a network of interwoven and/or interlaced fibers. A type oftextile may include a fabric, which is constructed by interlacing thefibers using specific techniques. These include weaving, knitting,crocheting, knotting, tatting, tufting, or braiding. Cloth may be usedsynonymously with fabric, although may specifically refer to a processedpiece of fabric. Other types of textiles may be constructed usingbonding (chemical, mechanical, heat, etc.), felting, or other nonwovenprocesses. Textiles created through one of these processes arefabric-like, and may be considered synonymous with fabric for thepurposes of this application.

5.9.1.2 Mechanical Properties

Resilience: Ability of a material to absorb energy when deformedelastically and to release the energy upon unloading.

Resilient: Will release substantially all of the energy when unloaded.Includes e.g. certain silicones, and thermoplastic elastomers.

Hardness: The ability of a material per se to resist deformation (e.g.described by a Young's Modulus, or an indentation hardness scalemeasured on a standardised sample size).

-   -   ‘Soft’ materials may include silicone or thermo-plastic        elastomer (TPE), and may, e.g. readily deform under finger        pressure.    -   ‘Hard’ materials may include polycarbonate, polypropylene, steel        or aluminium, and may not e.g. readily deform under finger        pressure.

Stiffness (or rigidity) of a structure or component: The ability of thestructure or component to resist deformation in response to an appliedload. The load may be a force or a moment, e.g. compression, tension,bending or torsion. The structure or component may offer differentresistances in different directions. The inverse of stiffness isflexibility.

Floppy structure or component: A structure or component that will changeshape, e.g. bend, when caused to support its own weight, within arelatively short period of time such as 1 second.

Rigid structure or component: A structure or component that will notsubstantially change shape when subject to the loads typicallyencountered in use. An example of such a use may be setting up andmaintaining a patient interface in sealing relationship with an entranceto a patient's airways, e.g. at a load of approximately 20 to 30 cmH₂Opressure.

As an example, an I-beam may comprise a different bending stiffness(resistance to a bending load) in a first direction in comparison to asecond, orthogonal direction. In another example, a structure orcomponent may be floppy in a first direction and rigid in a seconddirection.

5.9.2 Respiratory Cycle

Apnea: According to some definitions, an apnea is said to have occurredwhen flow falls below a predetermined threshold for a duration, e.g. 10seconds. An obstructive apnea will be said to have occurred when,despite patient effort, some obstruction of the airway does not allowair to flow. A central apnea will be said to have occurred when an apneais detected that is due to a reduction in breathing effort, or theabsence of breathing effort, despite the airway being patent. A mixedapnea occurs when a reduction or absence of breathing effort coincideswith an obstructed airway.

Breathing rate: The rate of spontaneous respiration of a patient,usually measured in breaths per minute.

Duty cycle: The ratio of inhalation time, Ti to total breath time, Ttot.

Effort (breathing): The work done by a spontaneously breathing personattempting to breathe.

Expiratory portion of a breathing cycle: The period from the start ofexpiratory flow to the start of inspiratory flow.

Flow limitation: Flow limitation will be taken to be the state ofaffairs in a patient's respiration where an increase in effort by thepatient does not give rise to a corresponding increase in flow. Whereflow limitation occurs during an inspiratory portion of the breathingcycle it may be described as inspiratory flow limitation. Where flowlimitation occurs during an expiratory portion of the breathing cycle itmay be described as expiratory flow limitation.

Types of flow limited inspiratory waveforms:

-   -   (i) Flattened: Having a rise followed by a relatively flat        portion, followed by a fall.    -   (ii) M-shaped: Having two local peaks, one at the leading edge,        and one at the trailing edge, and a relatively flat portion        between the two peaks.    -   (iii) Chair-shaped: Having a single local peak, the peak being        at the leading edge, followed by a relatively flat portion.    -   (iv) Reverse-chair shaped: Having a relatively flat portion        followed by single local peak, the peak being at the trailing        edge.

Hypopnea: According to some definitions, a hypopnea is taken to be areduction in flow, but not a cessation of flow. In one form, a hypopneamay be said to have occurred when there is a reduction in flow below athreshold rate for a duration. A central hypopnea will be said to haveoccurred when a hypopnea is detected that is due to a reduction inbreathing effort. In one form in adults, either of the following may beregarded as being hypopneas:

-   -   (i) a 30% reduction in patient breathing for at least 10 seconds        plus an associated 4% desaturation; or    -   (ii) a reduction in patient breathing (but less than 50%) for at        least 10 seconds, with an associated desaturation of at least 3%        or an arousal.

Hyperpnea: An increase in flow to a level higher than normal.

Inspiratory portion of a breathing cycle: The period from the start ofinspiratory flow to the start of expiratory flow will be taken to be theinspiratory portion of a breathing cycle.

Patency (airway): The degree of the airway being open, or the extent towhich the airway is open. A patent airway is open. Airway patency may bequantified, for example with a value of one (1) being patent, and avalue of zero (0), being closed (obstructed).

Positive End-Expiratory Pressure (PEEP): The pressure above atmospherein the lungs that exists at the end of expiration.

Peak flow rate (Qpeak): The maximum value of flow rate during theinspiratory portion of the respiratory flow waveform.

Respiratory flow rate, patient airflow rate, respiratory airflow rate(Qr): These terms may be understood to refer to the RPT device'sestimate of respiratory flow rate, as opposed to “true respiratory flowrate” or “true respiratory flow rate”, which is the actual respiratoryflow rate experienced by the patient, usually expressed in litres perminute.

Tidal volume (Vt): The volume of air inhaled or exhaled during normalbreathing, when extra effort is not applied. In principle theinspiratory volume Vi (the volume of air inhaled) is equal to theexpiratory volume Ve (the volume of air exhaled), and therefore a singletidal volume Vt may be defined as equal to either quantity. In practicethe tidal volume Vt is estimated as some combination, e.g. the mean, ofthe inspiratory volume Vi and the expiratory volume Ve.

(inhalation) Time (Ti): The duration of the inspiratory portion of therespiratory flow rate waveform.

(exhalation) Time (Te): The duration of the expiratory portion of therespiratory flow rate waveform.

(total) Time (Ttot): The total duration between the start of oneinspiratory portion of a respiratory flow rate waveform and the start ofthe following inspiratory portion of the respiratory flow rate waveform.

Typical recent ventilation: The value of ventilation around which recentvalues of ventilation Vent over some predetermined timescale tend tocluster, that is, a measure of the central tendency of the recent valuesof ventilation.

Upper airway obstruction (UAO): includes both partial and total upperairway obstruction. This may be associated with a state of flowlimitation, in which the flow rate increases only slightly or may evendecrease as the pressure difference across the upper airway increases(Starling resistor behaviour).

Ventilation (Vent): A measure of a rate of gas being exchanged by thepatient's respiratory system. Measures of ventilation may include one orboth of inspiratory and expiratory flow, per unit time. When expressedas a volume per minute, this quantity is often referred to as “minuteventilation”. Minute ventilation is sometimes given simply as a volume,understood to be the volume per minute.

5.9.3 Ventilation

Adaptive Servo-Ventilator (ASV): A servo-ventilator that has achangeable, rather than fixed target ventilation. The changeable targetventilation may be learned from some characteristic of the patient, forexample, a respiratory characteristic of the patient.

Backup rate: A parameter of a ventilator that establishes the minimumbreathing rate (typically in number of breaths per minute) that theventilator will deliver to the patient, if not triggered by spontaneousrespiratory effort.

Cycled: The termination of a ventilator's inspiratory phase. When aventilator delivers a breath to a spontaneously breathing patient, atthe end of the inspiratory portion of the breathing cycle, theventilator is said to be cycled to stop delivering the breath.

Expiratory positive airway pressure (EPAP): a base pressure, to which apressure varying within the breath is added to produce the desiredinterface pressure which the ventilator will attempt to achieve at agiven time.

End expiratory pressure (EEP): Desired interface pressure which theventilator will attempt to achieve at the end of the expiratory portionof the breath. If the pressure waveform template Π(Φ) is zero-valued atthe end of expiration, i.e. Π(Φ))=0 when Φ=1, the EEP is equal to theEPAP.

Inspiratory positive airway pressure (IPAP): Maximum desired interfacepressure which the ventilator will attempt to achieve during theinspiratory portion of the breath.

Pressure support: A number that is indicative of the increase inpressure during ventilator inspiration over that during ventilatorexpiration, and generally means the difference in pressure between themaximum value during inspiration and the base pressure (e.g.,PS=IPAP−EPAP). In some contexts pressure support means the differencewhich the ventilator aims to achieve, rather than what it actuallyachieves.

Servo-ventilator: A ventilator that measures patient ventilation, has atarget ventilation, and which adjusts the level of pressure support tobring the patient ventilation towards the target ventilation.

Spontaneous/Timed (S/T): A mode of a ventilator or other device thatattempts to detect the initiation of a breath of a spontaneouslybreathing patient. If however, the device is unable to detect a breathwithin a predetermined period of time, the device will automaticallyinitiate delivery of the breath.

Swing: Equivalent term to pressure support.

Triggered: When a ventilator, or other respiratory therapy device suchas an RPT device or portable oxygen concentrator, delivers a volume ofbreathable gas to a spontaneously breathing patient, it is said to betriggered to do so. Triggering usually takes place at or near theinitiation of the respiratory portion of the breathing cycle by thepatient's efforts.

5.9.4 Anatomy 5.9.4.1 Anatomy of the Face

Ala: the external outer wall or “wing” of each nostril (plural: alar)

Alare: The most lateral point on the nasal ala.

Alar curvature (or alar crest) point: The most posterior point in thecurved base line of each ala, found in the crease formed by the union ofthe ala with the cheek.

Auricle: The whole external visible part of the ear.

(nose) Bony framework: The bony framework of the nose comprises thenasal bones, the frontal process of the maxillae and the nasal part ofthe frontal bone.

(nose) Cartilaginous framework: The cartilaginous framework of the nosecomprises the septal, lateral, major and minor cartilages.

Columella: the strip of skin that separates the nares and which runsfrom the pronasale to the upper lip.

Columella angle: The angle between the line drawn through the midpointof the nostril aperture and a line drawn perpendicular to the Frankforthorizontal while intersecting subnasale.

Frankfort horizontal plane: A line extending from the most inferiorpoint of the orbital margin to the left tragion. The tragion is thedeepest point in the notch superior to the tragus of the auricle.

Glabella: Located on the soft tissue, the most prominent point in themidsagittal plane of the forehead.

Lateral nasal cartilage: A generally triangular plate of cartilage. Itssuperior margin is attached to the nasal bone and frontal process of themaxilla, and its inferior margin is connected to the greater alarcartilage.

Lip, lower (labrale inferius): A point on the face between the mouth andsupramenton, lying in the median sagittal plane.

Lip, upper (labrale superius): A point on the face between the mouth andnose, lying in the median sagittal plane.

Greater alar cartilage: A plate of cartilage lying below the lateralnasal cartilage. It is curved around the anterior part of the naris. Itsposterior end is connected to the frontal process of the maxilla by atough fibrous membrane containing three or four minor cartilages of theala.

Nares (Nostrils): Approximately ellipsoidal apertures forming theentrance to the nasal cavity. The singular form of nares is naris(nostril). The nares are separated by the nasal septum.

Naso-labial sulcus or Naso-labial fold: The skin fold or groove thatruns from each side of the nose to the corners of the mouth, separatingthe cheeks from the upper lip.

Naso-labial angle: The angle between the columella and the upper lip,while intersecting subnasale.

Otobasion inferior: The lowest point of attachment of the auricle to theskin of the face.

Otobasion superior: The highest point of attachment of the auricle tothe skin of the face.

Pronasale: the most protruded point or tip of the nose, which can beidentified in lateral view of the rest of the portion of the head.

Philtrum: the midline groove that runs from lower border of the nasalseptum to the top of the lip in the upper lip region.

Pogonion: Located on the soft tissue, the most anterior midpoint of thechin.

Ridge (nasal): The nasal ridge is the midline prominence of the nose,extending from the Sellion to the Pronas ale.

Sagittal plane: A vertical plane that passes from anterior (front) toposterior (rear). The midsagittal plane is a sagittal plane that dividesthe body into right and left halves.

Sellion: Located on the soft tissue, the most concave point overlyingthe area of the frontonasal suture.

Septal cartilage (nasal): The nasal septal cartilage forms part of theseptum and divides the front part of the nasal cavity.

Subalare: The point at the lower margin of the alar base, where the alarbase joins with the skin of the superior (upper) lip.

Subnasal point: Located on the soft tissue, the point at which thecolumella merges with the upper lip in the midsagittal plane.

Supramenton: The point of greatest concavity in the midline of the lowerlip between labrale inferius and soft tissue pogonion

5.9.4.2 Anatomy of the Skull

Frontal bone: The frontal bone includes a large vertical portion, thesquama frontalis, corresponding to the region known as the forehead.

Mandible: The mandible forms the lower jaw. The mental protuberance isthe bony protuberance of the jaw that forms the chin.

Maxilla: The maxilla forms the upper jaw and is located above themandible and below the orbits. The frontal process of the maxillaprojects upwards by the side of the nose, and forms part of its lateralboundary.

Nasal bones: The nasal bones are two small oblong bones, varying in sizeand form in different individuals; they are placed side by side at themiddle and upper part of the face, and form, by their junction, the“bridge” of the nose.

Nasion: The intersection of the frontal bone and the two nasal bones, adepressed area directly between the eyes and superior to the bridge ofthe nose.

Occipital bone: The occipital bone is situated at the back and lowerpart of the cranium. It includes an oval aperture, the foramen magnum,through which the cranial cavity communicates with the vertebral canal.The curved plate behind the foramen magnum is the squama occipitalis.

Orbit: The bony cavity in the skull to contain the eyeball.

Parietal bones: The parietal bones are the bones that, when joinedtogether, form the roof and sides of the cranium.

Temporal bones: The temporal bones are situated on the bases and sidesof the skull, and support that part of the face known as the temple.

Zygomatic bones: The face includes two zygomatic bones, located in theupper and lateral parts of the face and forming the prominence of thecheek.

5.9.4.3 Anatomy of the Respiratory System

Diaphragm: A sheet of muscle that extends across the bottom of the ribcage. The diaphragm separates the thoracic cavity, containing the heart,lungs and ribs, from the abdominal cavity. As the diaphragm contractsthe volume of the thoracic cavity increases and air is drawn into thelungs.

Larynx: The larynx, or voice box houses the vocal folds and connects theinferior part of the pharynx (hypopharynx) with the trachea.

Lungs: The organs of respiration in humans. The conducting zone of thelungs contains the trachea, the bronchi, the bronchioles, and theterminal bronchioles. The respiratory zone contains the respiratorybronchioles, the alveolar ducts, and the alveoli.

Nasal cavity: The nasal cavity (or nasal fossa) is a large air filledspace above and behind the nose in the middle of the face. The nasalcavity is divided in two by a vertical fin called the nasal septum. Onthe sides of the nasal cavity are three horizontal outgrowths callednasal conchae (singular “concha”) or turbinates. To the front of thenasal cavity is the nose, while the back blends, via the choanae, intothe nasopharynx.

Pharynx: The part of the throat situated immediately inferior to (below)the nasal cavity, and superior to the oesophagus and larynx. The pharynxis conventionally divided into three sections: the nasopharynx(epipharynx) (the nasal part of the pharynx), the oropharynx(mesopharynx) (the oral part of the pharynx), and the laryngopharynx(hypopharynx).

5.9.5 Patient Interface

Anti-asphyxia valve (AAV): The component or sub-assembly of a masksystem that, by opening to atmosphere in a failsafe manner, reduces therisk of excessive CO₂ rebreathing by a patient.

Elbow: An elbow is an example of a structure that directs an axis offlow of air travelling therethrough to change direction through anangle. In one form, the angle may be approximately 90 degrees. Inanother form, the angle may be more, or less than 90 degrees. The elbowmay have an approximately circular cross-section. In another form theelbow may have an oval or a rectangular cross-section. In certain formsan elbow may be rotatable with respect to a mating component, e.g. about360 degrees. In certain forms an elbow may be removable from a matingcomponent, e.g. via a snap connection. In certain forms, an elbow may beassembled to a mating component via a one-time snap during manufacture,but not removable by a patient.

Frame: Frame will be taken to mean a mask structure that bears the loadof tension between two or more points of connection with a headgear. Amask frame may be a non-airtight load bearing structure in the mask.However, some forms of mask frame may also be air-tight.

Headgear: Headgear will be taken to mean a form of positioning andstabilizing structure designed for use on a head. For example theheadgear may comprise a collection of one or more struts, ties andstiffeners configured to locate and retain a patient interface inposition on a patient's face for delivery of respiratory therapy. Someties are formed of a soft, flexible, elastic material such as alaminated composite of foam and fabric.

Membrane: Membrane will be taken to mean a typically thin element thathas, preferably, substantially no resistance to bending, but hasresistance to being stretched.

Plenum chamber: a mask plenum chamber will be taken to mean a portion ofa patient interface having walls at least partially enclosing a volumeof space, the volume having air therein pressurised above atmosphericpressure in use. A shell may form part of the walls of a mask plenumchamber.

Seal: May be a noun form (“a seal”) which refers to a structure, or averb form (“to seal”) which refers to the effect. Two elements may beconstructed and/or arranged to ‘seal’ or to effect ‘sealing’therebetween without requiring a separate ‘seal’ element per se.

Shell: A shell will be taken to mean a curved, relatively thin structurehaving bending, tensile and compressive stiffness. For example, a curvedstructural wall of a mask may be a shell. In some forms, a shell may befaceted. In some forms a shell may be airtight. In some forms a shellmay not be airtight.

Stiffener: A stiffener will be taken to mean a structural componentdesigned to increase the bending resistance of another component in atleast one direction.

Strut: A strut will be taken to be a structural component designed toincrease the compression resistance of another component in at least onedirection.

Swivel (noun): A subassembly of components configured to rotate about acommon axis, preferably independently, preferably under low torque. Inone form, the swivel may be constructed to rotate through an angle of atleast 360 degrees. In another form, the swivel may be constructed torotate through an angle less than 360 degrees. When used in the contextof an air delivery conduit, the sub-assembly of components preferablycomprises a matched pair of cylindrical conduits. There may be little orno leak flow of air from the swivel in use.

Tie (noun): A structure designed to resist tension.

Vent: (noun): A structure that allows a flow of air from an interior ofthe mask, or conduit, to ambient air for clinically effective washout ofexhaled gases. For example, a clinically effective washout may involve aflow rate of about 10 litres per minute to about 100 litres per minute,depending on the mask design and treatment pressure.

5.9.6 Shape of Structures

Products in accordance with the present technology may comprise one ormore three-dimensional mechanical structures, for example a mask cushionor an impeller. The three-dimensional structures may be bounded bytwo-dimensional surfaces. These surfaces may be distinguished using alabel to describe an associated surface orientation, location, function,or some other characteristic. For example a structure may comprise oneor more of an anterior surface, a posterior surface, an interior surfaceand an exterior surface. In another example, a seal-forming structuremay comprise a face-contacting (e.g. outer) surface, and a separatenon-face-contacting (e.g. underside or inner) surface. In anotherexample, a structure may comprise a first surface and a second surface.

To facilitate describing the shape of the three-dimensional structuresand the surfaces, we first consider a cross-section through a surface ofthe structure at a point, p. See FIG. 3B to FIG. 3F, which illustrateexamples of cross-sections at point p on a surface, and the resultingplane curves. FIGS. 3B to 3F also illustrate an outward normal vector atp. The outward normal vector at p points away from the surface. In someexamples we describe the surface from the point of view of an imaginarysmall person standing upright on the surface.

5.9.6.1 Curvature in One Dimension

The curvature of a plane curve at p may be described as having a sign(e.g. positive, negative) and a magnitude (e.g. 1/radius of a circlethat just touches the curve at p).

Positive curvature: If the curve at p turns towards the outward normal,the curvature at that point will be taken to be positive (if theimaginary small person leaves the point p they must walk uphill). SeeFIG. 3B (relatively large positive curvature compared to FIG. 3C) andFIG. 3C (relatively small positive curvature compared to FIG. 3B). Suchcurves are often referred to as concave.

Zero curvature: If the curve at p is a straight line, the curvature willbe taken to be zero (if the imaginary small person leaves the point p,they can walk on a level, neither up nor down). See FIG. 3D.

Negative curvature: If the curve at p turns away from the outwardnormal, the curvature in that direction at that point will be taken tobe negative (if the imaginary small person leaves the point p they mustwalk downhill). See FIG. 3E (relatively small negative curvaturecompared to FIG. 3F) and FIG. 3F (relatively large negative curvaturecompared to FIG. 3E). Such curves are often referred to as convex.

5.9.6.2 Curvature of Two Dimensional Surfaces

A description of the shape at a given point on a two-dimensional surfacein accordance with the present technology may include multiple normalcross-sections. The multiple cross-sections may cut the surface in aplane that includes the outward normal (a “normal plane”), and eachcross-section may be taken in a different direction. Each cross-sectionresults in a plane curve with a corresponding curvature. The differentcurvatures at that point may have the same sign, or a different sign.Each of the curvatures at that point has a magnitude, e.g. relativelysmall. The plane curves in FIGS. 3B to 3F could be examples of suchmultiple cross-sections at a particular point.

Principal curvatures and directions: The directions of the normal planeswhere the curvature of the curve takes its maximum and minimum valuesare called the principal directions. In the examples of FIG. 3B to FIG.3F, the maximum curvature occurs in FIG. 3B, and the minimum occurs inFIG. 3F, hence FIG. 3B and FIG. 3F are cross sections in the principaldirections. The principal curvatures at p are the curvatures in theprincipal directions.

Region of a surface: A connected set of points on a surface. The set ofpoints in a region may have similar characteristics, e.g. curvatures orsigns.

Saddle region: A region where at each point, the principal curvatureshave opposite signs, that is, one is positive, and the other is negative(depending on the direction to which the imaginary person turns, theymay walk uphill or downhill).

Dome region: A region where at each point the principal curvatures havethe same sign, e.g. both positive (a “concave dome”) or both negative (a“convex dome”).

Cylindrical region: A region where one principal curvature is zero (or,for example, zero within manufacturing tolerances) and the otherprincipal curvature is non-zero.

Planar region: A region of a surface where both of the principalcurvatures are zero (or, for example, zero within manufacturingtolerances).

Edge of a surface: A boundary or limit of a surface or region.

Path: In certain forms of the present technology, ‘path’ will be takento mean a path in the mathematical—topological sense, e.g. a continuousspace curve from f(0) to f(1) on a surface. In certain forms of thepresent technology, a ‘path’ may be described as a route or course,including e.g. a set of points on a surface. (The path for the imaginaryperson is where they walk on the surface, and is analogous to a gardenpath).

Path length: In certain forms of the present technology, ‘path length’will be taken to mean the distance along the surface from f(0) to f(1),that is, the distance along the path on the surface. There may be morethan one path between two points on a surface and such paths may havedifferent path lengths. (The path length for the imaginary person wouldbe the distance they have to walk on the surface along the path).

Straight-line distance: The straight-line distance is the distancebetween two points on a surface, but without regard to the surface. Onplanar regions, there would be a path on the surface having the samepath length as the straight-line distance between two points on thesurface. On non-planar surfaces, there may be no paths having the samepath length as the straight-line distance between two points. (For theimaginary person, the straight-line distance would correspond to thedistance ‘as the crow flies’.)

5.9.6.3 Space Curves

Space curves: Unlike a plane curve, a space curve does not necessarilylie in any particular plane. A space curve may be closed, that is,having no endpoints. A space curve may be considered to be aone-dimensional piece of three-dimensional space. An imaginary personwalking on a strand of the DNA helix walks along a space curve. Atypical human left ear comprises a helix, which is a left-hand helix,see FIG. 3Q. A typical human right ear comprises a helix, which is aright-hand helix, see FIG. 3R. FIG. 3S shows a right-hand helix. Theedge of a structure, e.g. the edge of a membrane or impeller, may followa space curve. In general, a space curve may be described by a curvatureand a torsion at each point on the space curve. Torsion is a measure ofhow the curve turns out of a plane. Torsion has a sign and a magnitude.The torsion at a point on a space curve may be characterised withreference to the tangent, normal and binormal vectors at that point.

Tangent unit vector (or unit tangent vector): For each point on a curve,a vector at the point specifies a direction from that point, as well asa magnitude. A tangent unit vector is a unit vector pointing in the samedirection as the curve at that point. If an imaginary person were flyingalong the curve and fell off her vehicle at a particular point, thedirection of the tangent vector is the direction she would betravelling.

Unit normal vector: As the imaginary person moves along the curve, thistangent vector itself changes. The unit vector pointing in the samedirection that the tangent vector is changing is called the unitprincipal normal vector. It is perpendicular to the tangent vector.

Binormal unit vector: The binormal unit vector is perpendicular to boththe tangent vector and the principal normal vector. Its direction may bedetermined by a right-hand rule (see e.g. FIG. 3P), or alternatively bya left-hand rule (FIG. 30 ).

Osculating plane: The plane containing the unit tangent vector and theunit principal normal vector. See FIGS. 30 and 3P.

Torsion of a space curve: The torsion at a point of a space curve is themagnitude of the rate of change of the binormal unit vector at thatpoint. It measures how much the curve deviates from the osculatingplane. A space curve which lies in a plane has zero torsion. A spacecurve which deviates a relatively small amount from the osculating planewill have a relatively small magnitude of torsion (e.g. a gently slopinghelical path). A space curve which deviates a relatively large amountfrom the osculating plane will have a relatively large magnitude oftorsion (e.g. a steeply sloping helical path). With reference to FIG.3S, since T2>T1, the magnitude of the torsion near the top coils of thehelix of FIG. 3S is greater than the magnitude of the torsion of thebottom coils of the helix of FIG. 3S

With reference to the right-hand rule of FIG. 3P, a space curve turningtowards the direction of the right-hand binormal may be considered ashaving a right-hand positive torsion (e.g. a right-hand helix as shownin FIG. 3S). A space curve turning away from the direction of theright-hand binormal may be considered as having a right-hand negativetorsion (e.g. a left-hand helix).

Equivalently, and with reference to a left-hand rule (see FIG. 30 ), aspace curve turning towards the direction of the left-hand binormal maybe considered as having a left-hand positive torsion (e.g. a left-handhelix). Hence left-hand positive is equivalent to right-hand negative.See FIG. 3T.

5.9.6.4 Holes

A surface may have a one-dimensional hole, e.g. a hole bounded by aplane curve or by a space curve. Thin structures (e.g. a membrane) witha hole, may be described as having a one-dimensional hole. See forexample the one dimensional hole in the surface of structure shown inFIG. 3I, bounded by a plane curve.

A structure may have a two-dimensional hole, e.g. a hole bounded by asurface. For example, an inflatable tyre has a two dimensional holebounded by the interior surface of the tyre. In another example, abladder with a cavity for air or gel could have a two-dimensional hole.See for example the cushion of FIG. 3L and the example cross-sectionstherethrough in FIG. 3M and FIG. 3N, with the interior surface boundinga two dimensional hole indicated. In a yet another example, a conduitmay comprise a one-dimension hole (e.g. at its entrance or at its exit),and a two-dimension hole bounded by the inside surface of the conduit.See also the two dimensional hole through the structure shown in FIG.3K, bounded by a surface as shown.

5.10 Other Remarks

A portion of the disclosure of this patent document contains materialwhich is subject to copyright protection. The copyright owner has noobjection to the facsimile reproduction by anyone of the patent documentor the patent disclosure, as it appears in Patent Office patent files orrecords, but otherwise reserves all copyright rights whatsoever.

Unless the context clearly dictates otherwise and where a range ofvalues is provided, it is understood that each intervening value, to thetenth of the unit of the lower limit, between the upper and lower limitof that range, and any other stated or intervening value in that statedrange is encompassed within the technology. The upper and lower limitsof these intervening ranges, which may be independently included in theintervening ranges, are also encompassed within the technology, subjectto any specifically excluded limit in the stated range. Where the statedrange includes one or both of the limits, ranges excluding either orboth of those included limits are also included in the technology.

Furthermore, where a value or values are stated herein as beingimplemented as part of the technology, it is understood that such valuesmay be approximated, unless otherwise stated, and such values may beutilized to any suitable significant digit to the extent that apractical technical implementation may permit or require it.

Furthermore, “approximately”, “substantially”, “about”, or any similarterm as used herein means +/−5 to +/−10% of the recited value.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this technology belongs. Although any methods andmaterials similar or equivalent to those described herein can also beused in the practice or testing of the present technology, a limitednumber of the exemplary methods and materials are described herein.

When a particular material is identified as being used to construct acomponent, obvious alternative materials with similar properties may beused as a substitute. Furthermore, unless specified to the contrary, anyand all components herein described are understood to be capable ofbeing manufactured and, as such, may be manufactured together orseparately.

It must be noted that as used herein and in the appended claims, thesingular forms “a”, “an”, and “the” include their plural equivalents,unless the context clearly dictates otherwise.

All publications mentioned herein are incorporated herein by referencein their entirety to disclose and describe the methods and/or materialswhich are the subject of those publications. The publications discussedherein are provided solely for their disclosure prior to the filing dateof the present application. Nothing herein is to be construed as anadmission that the present technology is not entitled to antedate suchpublication by virtue of prior invention. Further, the dates ofpublication provided may be different from the actual publication dates,which may need to be independently confirmed.

The terms “comprises” and “comprising” should be interpreted asreferring to elements, components, or steps in a non-exclusive manner,indicating that the referenced elements, components, or steps may bepresent, or utilized, or combined with other elements, components, orsteps that are not expressly referenced.

The subject headings used in the detailed description are included onlyfor the ease of reference of the reader and should not be used to limitthe subject matter found throughout the disclosure or the claims. Thesubject headings should not be used in construing the scope of theclaims or the claim limitations.

Although the technology herein has been described with reference toparticular examples, it is to be understood that these examples aremerely illustrative of the principles and applications of thetechnology. In some instances, the terminology and symbols may implyspecific details that are not required to practice the technology. Forexample, although the terms “first” and “second” may be used, unlessotherwise specified, they are not intended to indicate any order but maybe utilised to distinguish between distinct elements. Furthermore,although process steps in the methodologies may be described orillustrated in an order, such an ordering is not required. Those skilledin the art will recognize that such ordering may be modified and/oraspects thereof may be conducted concurrently or even synchronously.

It is therefore to be understood that numerous modifications may be madeto the illustrative examples and that other arrangements may be devisedwithout departing from the spirit and scope of the technology.

5.11 REFERENCE SIGNS LIST

curve 35 transition portion 36 wale 70 course 80 basic closed loop warpknit 90 weft knit 100 patient 1000 bed partner 1100 face 1300 patientinterface 3000 seal-forming structure 3100 cavity 3101 naris openings3102 bridge portion 3104 cushion assembly 3105 plenum chamber connectionopening 3106 support structure 3120 lateral support region 3122proximate end 3124 second wall 3126 textile membrane 3130 grip pad 3150space 3180 non-usable portion 3184 area 3188 area 3190 inner surface3194 outer surface 3195 outer surface 3196 inner surface 3197 plenumchamber 3200 plenum chamber lateral ends 3202 plenum chamber connector3204 notch 3206 edge 3208 slot 3209 chord 3210 superior point 3220inferior point 3230 lateral side 3250 corner regions 3252 medialsubnasale region 3260 pronasale region 3270 positioning and stabilizingstructure 3300 lateral portions 3302 superior portions 3304 hub 3306 tab3308 posterior strap 3310 end portion 3311 sleeves 3312 lateral end 3314headgear tubes 3350 vent 3400 structure vent 3402 structure 3500 swivel3502 depressing buttons 3504 connection port 3600 forehead support 3700ISO 3744 RPT device 4000 external housing 4010 upper portion 4012 lowerportion 4014 panel 4015 chassis 4016 handle 4018 pneumatic block 4020air filter 4110 inlet air filter 4112 outlet air filter 4114 muffler4120 inlet muffler 4122 outlet muffler 4124 pressure generator 4140blower 4142 motor 4144 anti-spill back valve 4160 air circuit 4170 aircircuit 4171 supplementary gas 4180 electrical components 4200 singlePrinted Circuit Board Assembly 4202 power supply 4210 input device 4220transducer 4270 humidifier 5000 patient interface 6000 cavity 6001seal-forming structure 6100 nasal portion 6101 oral portion 6102 narisopenings 6103 oral portion hole 6104 cushion assembly 6105 bridgeportion 6106 support structure 6120 cushion 6121 cushion 6122 textilemembrane 6130 sealing portion 6130 first sealing portion 6131 secondsealing portion 6132 plenum chamber 6200 positioning and stabilizingstructure 6300 left arm 6305 right arm 6307 joints 6312 tube 6348 tube6350 inner layer 6352 outer layer 6354 textile sheet 6360 membrane 6362tube sheet 6364 outer covering 6366 membrane 6368 membrane 6370 airpassage 6372 vent 6400 connection port 6600 conduit connector 6800conduit connector housing 6801 conduit connection end 6802 conduitconnector inlet hole 6803 one conduit connector vent hole 6831anti-asphyxia valve 6850 cavity 9001 seal-forming structure 9100 nasalportion 9101 oral portion 9102 nasal portion holes 9103 oral portionhole 9104 cushion assembly 9105 bridge portion 9106 support structure9120 textile membrane 9130 first sealing portion 9131 second sealingportion 9132 grip pad 9150 plenum chamber 9200 plenum chamber hole 9210positioning and stabilizing strucutre 9300 clip 9301 upper strap 9302lower strap 9303 connector 9304 vent 9400 vent 9404 connection port 9600conduit connector 9800 conduit 9900 sleeve 9901 tie connectors 9902connection port housing 9903 first curvature 10000 support structure10120 sealing portion 10130 air impermeable material 10131 textilematerial 10133 first layer 10133a second layer 10133b third layer 10133ctextile membrane 10135 first axis 11000 axis 11500 second axis 12000third axis 13000 fourth axis 14000 fifth axis 15000 second curvature20000 patient interface 21000 cavity 21001 seal-forming structure 21100nasal portion 21101 oral portion 21102 naris openings 21103 oral portionhole 21104 cushion assembly 21105 bridge portion 21106 support structure21120 sealing portion 21130 first sealing portion 21131 second sealingportion 21132 plenum chamber 21200 gap 21190 patient interface 23000cavity 23001 seal-forming structure 23100 nasal portion 23101 oralportion 23102 naris openings 23103 oral portion hole 23104 cushionassembly 23105 bridge portion 23106 support structure 23120 sealingportion 23130 first sealing portion 23131 second sealing portion 23132inner edge 23182 lower edge 23184 gap 23190 plenum chamber 23200 patientinterface 25000 cavity 25001 seal-forming structure 25100 nasal portion25101 oral portion 25102 naris openings 25103 oral portion hole 25104cushion assembly 25105 bridge portion 25106 support structure 25120sealing portion 25130 sealing portion 25130-1 first sealing portion25131 second sealing portion 25132 support rib 25186 secondary rib 25188insert 25194 plenum chamber 25200 lateral side 25250 corner region 25252third curvature 30000 fourth curvature 40000 fifth curvature 50000 arch60000 first height H₁ second height H₂ first impermeable thicknessT_(I1) second impermeable thickness T_(I2)

1-24. (canceled)
 25. A cushion assembly for delivery of a flow of air ata continuously positive pressure with respect to ambient air pressure toan entrance to a patient's nares and to an entrance to the patient'smouth, the cushion assembly comprising: a plenum chamber at leastpartially forming a cavity pressurisable to a therapeutic pressure of atleast 6 cmH2O above ambient air pressure, said plenum chamber includingat least one plenum chamber inlet port sized and structured to receive aflow of air at the therapeutic pressure for breathing by the patient;and a seal-forming structure comprising a silicone support structure anda textile membrane, the textile membrane being constructed and arrangedto, in use, form a pressure-assisted seal with the patient's face, thetextile membrane comprising: a nasal portion configured to, in use, forma pressure-assisted seal with a region of the patient's face around theentrance to the patient's nares, the nasal portion including two narisopenings and a bridge portion positioned between the naris openings, thetwo naris openings being arranged to deliver the flow of air to theentrance to the patient's nares in use, and an oral portion configuredto, in use, form a pressure-assisted seal with a region of the patient'sface around the entrance to the patient's mouth, the oral portionincluding an oral portion hole formed therein such that the oral portionencircles the oral portion hole, the oral portion hole being arranged todeliver the flow of air to the entrance to the patient's mouth in use.26. The cushion assembly of claim 25, wherein the nasal portion isconfigured to, in use, form the seal only on portions of the patient'sface inferior to a nasal bridge region of the patient.
 27. The cushionassembly of claim 26, wherein the nasal portion is configured to formthe seal with an underside of the patient's nose at or below thepatient's pronasale in use.
 28. The cushion assembly according to claim25, wherein the bridge portion limits the patient's nose from enteringinto the cavity during use.
 29. The cushion assembly according to claim25, wherein the textile membrane is air impermeable.
 30. The cushionassembly according to claim 25, wherein the textile membrane isconnected to the support structure at an overlapping region, the textilemembrane including a textile material that overlaps with an edge portionof the support structure.
 31. The cushion assembly according to claim25, wherein the textile membrane includes a textile material and an airimpermeable layer.
 22. The cushion assembly according to claim 30,wherein the textile material is a single, continuous piece of materialand is used to form both the nasal portion and the oral portion of thetextile membrane.
 33. The cushion assembly according to claim 25,wherein the at least one plenum chamber inlet port comprises two plenumchamber inlet ports formed in respective lateral sides of the plenumchamber.
 34. The cushion assembly according to claim 25, wherein each ofthe naris openings is configured to be positioned adjacent to one of thepatient's nares in use.
 35. The cushion assembly according to claim 25,wherein the textile membrane includes a first portion held in a relaxedstate and a second portion held in a taut state, the taut state of thesecond portion causing the seal-forming structure to have athree-dimensional shape with multiple curvatures.
 36. The cushionassembly of claim 35, wherein the bridge portion is the second portionand is held in a taut state.
 37. The cushion assembly according to claim35, wherein the bridge portion is crimped.
 38. The cushion assemblyaccording to claim 35, wherein the first portion is at least partiallycomprised of the oral portion.
 39. The cushion assembly according toclaim 35, wherein the textile membrane is curved about at least twonon-parallel axes as a result of the taut state of the second portion inorder to form the three-dimensional shape.
 40. The cushion assemblyaccording to claim 35, wherein the support structure is configured tohold the textile membrane in the three-dimensional shape.
 41. Thecushion assembly according to claim 25, wherein the seal-formingstructure includes a pair of ribs projecting inwardly into the cavityfrom an inner surface of the support structure on respective lateralsides of the plenum chamber, the ribs being configured to increasestiffness of the cushion assembly.
 42. The cushion assembly according toclaim 25, wherein the nasal portion is configured to press against thepatient's face such that the patient's nose is not received in thecavity.
 43. The cushion assembly according to claim 1, wherein only thetextile membrane of the cushion assembly seals with the patient's face.44. A patient interface for delivering a flow of air at positivepressure to a patient for treatment of sleep disordered breathing, thepatient interface comprising: the cushion assembly of claim 25; and apositioning and stabilising structure to provide a force to hold theseal-forming structure in a therapeutically effective position on thepatient's head,
 45. The patient interface of claim 44, wherein thepositioning and stabilising structure comprising a pair of conduits fordelivering the flow of air to the cushion assembly in use, the pair ofconduits being configured to extend along respective sides of thepatient's head when the patient interface is worn.
 46. The patientinterface of claim 45, wherein the at least one plenum chamber inletport comprises two plenum chamber inlet ports formed in respectivelateral sides of the plenum chamber, and wherein the conduits areconfigured to respectively connect to the plenum chamber inlet ports.